Merge pull request #243 from armel/feature_update_v5

Feature update v5

.gitignore

@@ -7,6 +7,7 @@ firmware
 .cache
 compile_commands.json
 .vscode
+.claude
 /docs
 k5_eeprom.raw
 

App/CMakeLists.txt

@@ -161,6 +161,7 @@ enable_feature(ENABLE_SQUELCH_MORE_SENSITIVE)
 enable_feature(ENABLE_FASTER_CHANNEL_SCAN)
 enable_feature(ENABLE_RSSI_BAR)
 enable_feature(ENABLE_AUDIO_BAR)
+enable_feature(ENABLE_FEAT_F4HWN_AUDIO_SCOPE)
 enable_feature(ENABLE_COPY_CHAN_TO_VFO)
 enable_feature(ENABLE_REDUCE_LOW_MID_TX_POWER)
 enable_feature(ENABLE_BYP_RAW_DEMODULATORS)
@@ -201,6 +202,7 @@ enable_feature(ENABLE_FEAT_F4HWN_PMR)
 enable_feature(ENABLE_FEAT_F4HWN_GMRS_FRS_MURS)
 enable_feature(ENABLE_FEAT_F4HWN_CA)
 enable_feature(ENABLE_FEAT_F4HWN_DEBUG)
+enable_feature(ENABLE_FEAT_F4HWN_MEM)
 
 # ---- DEBUGGING ----
 

App/app/action.c

@@ -236,7 +236,7 @@ void ACTION_Scan(bool bRestart)
         }
 
         // channel mode. Keep scanning but toggle between scan lists
-        RADIO_NextValidList();
+        RADIO_NextValidList(1);
 
         #ifdef ENABLE_FEAT_F4HWN_RESUME_STATE
             SETTINGS_WriteCurrentState();
@@ -290,6 +290,8 @@ void ACTION_SwitchDemodul(void)
 
 void ACTION_Handle(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
 {
+    HideFKeyIcon();
+
     if (gScreenToDisplay == DISPLAY_MAIN && gDTMF_InputMode){
          // entering DTMF code
 
@@ -319,19 +321,23 @@ void ACTION_Handle(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
         return;
     }
 
-    enum ACTION_OPT_t funcShort = ACTION_OPT_NONE;
-    enum ACTION_OPT_t funcLong  = ACTION_OPT_NONE;
+    enum ACTION_OPT_t func = ACTION_OPT_NONE;
     switch(Key) {
         case KEY_SIDE1:
-            funcShort = gEeprom.KEY_1_SHORT_PRESS_ACTION;
-            funcLong  = gEeprom.KEY_1_LONG_PRESS_ACTION;
+            if (bKeyHeld)
+                func = gEeprom.KEY_1_LONG_PRESS_ACTION;
+            else
+                func = gEeprom.KEY_1_SHORT_PRESS_ACTION;
             break;
         case KEY_SIDE2:
-            funcShort = gEeprom.KEY_2_SHORT_PRESS_ACTION;
-            funcLong  = gEeprom.KEY_2_LONG_PRESS_ACTION;
+            if (bKeyHeld)
+                func = gEeprom.KEY_2_LONG_PRESS_ACTION;
+            else
+                func = gEeprom.KEY_2_SHORT_PRESS_ACTION;
             break;
         case KEY_MENU:
-            funcLong  = gEeprom.KEY_M_LONG_PRESS_ACTION;
+            if (bKeyHeld)
+                func = gEeprom.KEY_M_LONG_PRESS_ACTION;
             break;
         default:
             break;
@@ -347,17 +353,46 @@ void ACTION_Handle(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
     if(!(bKeyHeld && !bKeyPressed)) // don't beep on released after hold
         gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
 
-    if (bKeyHeld || bKeyPressed) // held
+    if (bKeyHeld && !bKeyPressed) // button released after hold
     {
-        funcShort = funcLong;
-
-        if (!bKeyPressed) //ignore release if held
-            return;
+        return;
     }
 
     // held or released after short press beyond this point
+    
+#ifdef ENABLE_FMRADIO
+    if (gFmRadioMode) { // do not run these actions in FM radio mode
+        switch (func) {
+            case ACTION_OPT_POWER:
+            case ACTION_OPT_MONITOR:
+            case ACTION_OPT_A_B:
+            case ACTION_OPT_VFO_MR:
+            case ACTION_OPT_SWITCH_DEMODUL:
+    #ifdef ENABLE_VOX
+            case ACTION_OPT_VOX:
+    #endif
+    #ifdef ENABLE_FEAT_F4HWN
+            case ACTION_OPT_RXMODE:
+            case ACTION_OPT_MAINONLY:
+            case ACTION_OPT_WN:
+        #ifdef ENABLE_FEAT_F4HWN_AUDIO
+            case ACTION_OPT_RXA:
+        #endif
+        #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
+            case ACTION_OPT_POWER_HIGH:
+            case ACTION_OPT_REMOVE_OFFSET:
+        #endif
+    #endif
+                gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
+                return;
 
-    action_opt_table[funcShort]();
+            default:
+                break;
+        }
+    }
+#endif
+
+    action_opt_table[func]();
 }
 
 
@@ -503,17 +538,13 @@ void ACTION_RxMode(void)
 {
     static bool cycle = 0;
 
-    switch(cycle) {
-        case 0:
-            gEeprom.DUAL_WATCH = !gEeprom.DUAL_WATCH;
-            cycle = 1;
-            break;
-        case 1:
-            gEeprom.CROSS_BAND_RX_TX = !gEeprom.CROSS_BAND_RX_TX;
-            cycle = 0;
-            break;
+    if (cycle) {
+        gEeprom.CROSS_BAND_RX_TX = !gEeprom.CROSS_BAND_RX_TX;
+    } else {
+        gEeprom.DUAL_WATCH = !gEeprom.DUAL_WATCH;
     }
 
+    cycle = !cycle;
     ACTION_Update();
 }
 
@@ -523,22 +554,18 @@ void ACTION_MainOnly(void)
     static uint8_t dw = 0;
     static uint8_t cb = 0;
 
-    switch(cycle) {
-        case 0:
-            dw = gEeprom.DUAL_WATCH;
-            cb = gEeprom.CROSS_BAND_RX_TX;
+    if (cycle) {
+        gEeprom.DUAL_WATCH = dw;
+        gEeprom.CROSS_BAND_RX_TX = cb;
+    } else {
+        dw = gEeprom.DUAL_WATCH;
+        cb = gEeprom.CROSS_BAND_RX_TX;
 
-            gEeprom.DUAL_WATCH = 0;
-            gEeprom.CROSS_BAND_RX_TX = 0;
-            cycle = 1;
-            break;
-        case 1:
-            gEeprom.DUAL_WATCH = dw;
-            gEeprom.CROSS_BAND_RX_TX = cb;
-            cycle = 0;
-            break;
+        gEeprom.DUAL_WATCH = 0;
+        gEeprom.CROSS_BAND_RX_TX = 0;
     }
 
+    cycle = !cycle;
     ACTION_Update();
 }
 
@@ -553,64 +580,36 @@ void ACTION_RxA(void)
 void ACTION_Ptt(void)
 {
     gSetting_set_ptt_session = !gSetting_set_ptt_session;
+
+    ACTION_Update();
 }
 
 void ACTION_Wn(void)
 {
-    if (gRxVfo->Modulation == MODULATION_AM)
+    const bool isRx = FUNCTION_IsRx();
+    VFO_Info_t *pVfo = isRx ? gRxVfo : gTxVfo;
+
+    pVfo->CHANNEL_BANDWIDTH = !pVfo->CHANNEL_BANDWIDTH;
+
+    if (pVfo->Modulation == MODULATION_AM)
     {
         BK4819_SetFilterBandwidth(BK4819_FILTER_BW_AM, true);
         return;
     }
+
+    uint8_t bw = pVfo->CHANNEL_BANDWIDTH;
+
     #ifdef ENABLE_FEAT_F4HWN_NARROWER
-        bool narrower = 0;
-        if (FUNCTION_IsRx())
+        if (isRx && bw == BANDWIDTH_NARROW && gSetting_set_nfm == 1)
         {
-            gRxVfo->CHANNEL_BANDWIDTH = (gRxVfo->CHANNEL_BANDWIDTH == 0) ? 1: 0;
-            if(gRxVfo->CHANNEL_BANDWIDTH == BANDWIDTH_NARROW && gSetting_set_nfm == 1)
-            {
-                narrower = 1;
-            }
-
-            #ifdef ENABLE_AM_FIX
-                BK4819_SetFilterBandwidth(gRxVfo->CHANNEL_BANDWIDTH + narrower, true);
-            #else
-                BK4819_SetFilterBandwidth(gRxVfo->CHANNEL_BANDWIDTH + narrower, false);
-            #endif
+            bw++; 
         }
-        else
-        {
-            gTxVfo->CHANNEL_BANDWIDTH = (gTxVfo->CHANNEL_BANDWIDTH == 0) ? 1: 0;
-            if(gTxVfo->CHANNEL_BANDWIDTH == BANDWIDTH_NARROW && gSetting_set_nfm == 1)
-            {
-                narrower = 1;
-            }
+    #endif
 
-            #ifdef ENABLE_AM_FIX
-                BK4819_SetFilterBandwidth(gTxVfo->CHANNEL_BANDWIDTH, true);
-            #else
-                BK4819_SetFilterBandwidth(gTxVfo->CHANNEL_BANDWIDTH, false);
-            #endif
-        }
+    #ifdef ENABLE_AM_FIX
+        BK4819_SetFilterBandwidth(bw, true);
     #else
-        if (FUNCTION_IsRx())
-        {
-            gRxVfo->CHANNEL_BANDWIDTH = (gRxVfo->CHANNEL_BANDWIDTH == 0) ? 1: 0;
-            #ifdef ENABLE_AM_FIX
-                BK4819_SetFilterBandwidth(gRxVfo->CHANNEL_BANDWIDTH, true);
-            #else
-                BK4819_SetFilterBandwidth(gRxVfo->CHANNEL_BANDWIDTH, false);
-            #endif
-        }
-        else
-        {
-            gTxVfo->CHANNEL_BANDWIDTH = (gTxVfo->CHANNEL_BANDWIDTH == 0) ? 1: 0;
-            #ifdef ENABLE_AM_FIX
-                BK4819_SetFilterBandwidth(gTxVfo->CHANNEL_BANDWIDTH, true);
-            #else
-                BK4819_SetFilterBandwidth(gTxVfo->CHANNEL_BANDWIDTH, false);
-            #endif
-        }
+        BK4819_SetFilterBandwidth(bw, false);
     #endif
 }
 

App/app/aircopy.c

@@ -89,12 +89,13 @@ DECLARE_AIRCOPY_BANK(1)
 
 static const AIRCOPY_Segment_t AIRCOPY_Segments_Settings[] = {
     { 0xA000, 0xA170, AIRCOPY_WRITE_BYTES },
+    { 0x880E, 0x886E, AIRCOPY_WRITE_BYTES },
 };
 
 static const AIRCOPY_TransferMap_t AIRCOPY_Map_Settings = {
     .segments = AIRCOPY_Segments_Settings,
-    .num_segments = 1,
-    .total_blocks = 6
+    .num_segments = 2,
+    .total_blocks = 8
 };
 
 // Finally
@@ -138,7 +139,7 @@ static void AIRCOPY_clear()
         crc[i] = 0;
     }
     #ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
-        getScreenShot(true);
+        SCREENSHOT_Update(true);
     #endif
 }
 
@@ -166,11 +167,18 @@ static inline void AIRCOPY_CheckComplete(void)
     {
         gAircopyState = AIRCOPY_COMPLETE;
 #ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
-        getScreenShot(false);
+        SCREENSHOT_Update(false);
 #endif
     }
 }
 
+static inline void AIRCOPY_Obfuscation(void)
+{
+    for (unsigned int i = 0; i < 34; i++) {
+        g_FSK_Buffer[i + 1] ^= Obfuscation[i % 8];
+    }
+}
+
 // ============================================================================
 // Send/Receive Functions
 // ============================================================================
@@ -211,7 +219,7 @@ bool AIRCOPY_SendMessage(void)
     if (CurrentSegmentIndex >= map->num_segments) {
         gAircopyState = AIRCOPY_COMPLETE;
         #ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
-            getScreenShot(false);
+            SCREENSHOT_Update(false);
         #endif
         return 0;
     }
@@ -222,9 +230,7 @@ bool AIRCOPY_SendMessage(void)
 
     g_FSK_Buffer[34] = CRC_Calculate(&g_FSK_Buffer[1], 2 + 64);
 
-    for (unsigned int i = 0; i < 34; i++) {
-        g_FSK_Buffer[i + 1] ^= Obfuscation[i % 8];
-    }
+    AIRCOPY_Obfuscation();
 
     RADIO_SetTxParameters();
 
@@ -260,9 +266,7 @@ void AIRCOPY_StorePacket(void)
         return;
     }
 
-    for (unsigned int i = 0; i < 34; i++) {
-        g_FSK_Buffer[i + 1] ^= Obfuscation[i % 8];
-    }
+    AIRCOPY_Obfuscation();
 
     uint16_t Crc = CRC_Calculate(&g_FSK_Buffer[1], 2 + 64);
     if (g_FSK_Buffer[34] != Crc) {
@@ -272,25 +276,9 @@ void AIRCOPY_StorePacket(void)
     }
 
     uint16_t Offset = g_FSK_Buffer[1];
-    const AIRCOPY_TransferMap_t *map = AIRCOPY_GetCurrentMap();
-
-    // Validate offset is in the map
-    bool validOffset = false;
-    for (uint16_t i = 0; i < map->num_segments; i++) {
-        if (Offset >= map->segments[i].start_offset && Offset < map->segments[i].end_offset) {
-            validOffset = true;
-            break;
-        }
-    }
-
-    if (!validOffset) {
-        gErrorsDuringAirCopy++;
-        AIRCOPY_CheckComplete();
-        return;
-    }
 
     const AIRCOPY_Segment_t *seg = AIRCOPY_FindSegmentForOffset(Offset);
-
+    
     if (seg == NULL) {
         gErrorsDuringAirCopy++;
         AIRCOPY_CheckComplete();
@@ -324,20 +312,27 @@ void AIRCOPY_StorePacket(void)
     AIRCOPY_CheckComplete();
 }
 
+static void AIRCOPY_InitTransfer(bool isSendMode)
+{
+    gAircopyStep = 1;
+    gFSKWriteIndex = 0;
+    gAirCopyBlockNumber = 0;
+    gInputBoxIndex = 0;
+    gAirCopyIsSendMode = isSendMode;
+
+    AIRCOPY_clear();
+    
+    gAircopyState = AIRCOPY_TRANSFER;
+}
+
 // ============================================================================
 // Key Processing
 // ============================================================================
 
-static void AIRCOPY_Key_DIGITS(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
+static void AIRCOPY_Key_DIGITS(KEY_Code_t Key)
 {
-    if (bKeyHeld || !bKeyPressed) {
-        return;
-    }
-
     INPUTBOX_Append(Key);
 
-    gRequestDisplayScreen = DISPLAY_AIRCOPY;
-
     if (gInputBoxIndex < 6) {
 #ifdef ENABLE_VOICE
         gAnotherVoiceID = (VOICE_ID_t)Key;
@@ -372,62 +367,34 @@ static void AIRCOPY_Key_DIGITS(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
         BK4819_ResetFSK();
         return;
     }
-
-    gRequestDisplayScreen = DISPLAY_AIRCOPY;
 }
 
-static void AIRCOPY_Key_EXIT(bool bKeyPressed, bool bKeyHeld)
+static void AIRCOPY_Key_EXIT()
 {
-    if (bKeyHeld || !bKeyPressed) {
-        return;
-    }
-
     if (gInputBoxIndex == 0) {
-        gAircopyStep = 1;
-        gFSKWriteIndex = 0;
-        gAirCopyBlockNumber = 0;
-        gInputBoxIndex = 0;
+        AIRCOPY_InitTransfer(0); // Mode: Receive
         gErrorsDuringAirCopy = lErrorsDuringAirCopy = 0;
-        gAirCopyIsSendMode = 0;
-
-        AIRCOPY_clear();
 
         BK4819_PrepareFSKReceive();
-
-        gAircopyState = AIRCOPY_TRANSFER;
+        
     } else {
         gInputBox[--gInputBoxIndex] = 10;
     }
-
-    gRequestDisplayScreen = DISPLAY_AIRCOPY;
 }
 
-static void AIRCOPY_Key_MENU(bool bKeyPressed, bool bKeyHeld)
+static void AIRCOPY_Key_MENU()
 {
-    if (bKeyHeld || !bKeyPressed) {
-        return;
-    }
-
-    gAircopyStep = 1;
-    gFSKWriteIndex = 0;
-    gAirCopyBlockNumber = 0;
-    gInputBoxIndex = 0;
-    gAirCopyIsSendMode = 1;
+    AIRCOPY_InitTransfer(1); // Mode: Send
+    
     g_FSK_Buffer[0] = 0xABCD;
     g_FSK_Buffer[1] = 0;
     g_FSK_Buffer[35] = 0xDCBA;
-
-    AIRCOPY_clear();
-
-    GUI_DisplayScreen();
-
-    gAircopyState = AIRCOPY_TRANSFER;
 }
 
-static void AIRCOPY_Key_UP_DOWN(bool bKeyPressed, bool bKeyHeld, int8_t Direction)
+static void AIRCOPY_Key_UP_DOWN(int8_t Direction)
 {
-    if (bKeyHeld || !bKeyPressed) {
-        return;
+    if (!gEeprom.SET_NAV) {
+        Direction = -Direction;
     }
 
     switch(Direction)
@@ -439,46 +406,40 @@ static void AIRCOPY_Key_UP_DOWN(bool bKeyPressed, bool bKeyHeld, int8_t Directio
             gAircopyCurrentMapIndex = (gAircopyCurrentMapIndex + AIRCOPY_NUM_MAPS - 1) % AIRCOPY_NUM_MAPS;
             break;
     }
-
-    gRequestDisplayScreen = DISPLAY_AIRCOPY;
 }
 
 void AIRCOPY_ProcessKeys(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
 {
+    if (bKeyHeld || !bKeyPressed) {
+        return;
+    }
+
+    if (Key != KEY_PTT) {
+        gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
+    }
+
     switch (Key) {
-    case KEY_0:
-    case KEY_1:
-    case KEY_2:
-    case KEY_3:
-    case KEY_4:
-    case KEY_5:
-    case KEY_6:
-    case KEY_7:
-    case KEY_8:
-    case KEY_9:
-        AIRCOPY_Key_DIGITS(Key, bKeyPressed, bKeyHeld);
+    case KEY_0...KEY_9:
+        AIRCOPY_Key_DIGITS(Key);
         break;
     case KEY_MENU:
-        AIRCOPY_Key_MENU(bKeyPressed, bKeyHeld);
+        AIRCOPY_Key_MENU();
         break;
     case KEY_EXIT:
-        AIRCOPY_Key_EXIT(bKeyPressed, bKeyHeld);
+        AIRCOPY_Key_EXIT();
         break;
     case KEY_UP:
-        if(gEeprom.SET_NAV == 0)
-            AIRCOPY_Key_UP_DOWN(bKeyPressed, bKeyHeld, -1);
-        else
-            AIRCOPY_Key_UP_DOWN(bKeyPressed, bKeyHeld, 1);
-        break;
     case KEY_DOWN:
-        if(gEeprom.SET_NAV == 0)
-            AIRCOPY_Key_UP_DOWN(bKeyPressed, bKeyHeld, 1);
-        else
-            AIRCOPY_Key_UP_DOWN(bKeyPressed, bKeyHeld, -1);
+        AIRCOPY_Key_UP_DOWN(Key == KEY_UP ? 1 : -1);
+        break;
+    case KEY_PTT:
         break;
     default:
+        gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
         break;
     }
+
+    gRequestDisplayScreen = DISPLAY_AIRCOPY;
 }
 
 #endif

App/app/app.c

@@ -273,18 +273,9 @@ static void HandleReceive(void)
             break;
 
         case CODE_TYPE_CONTINUOUS_TONE:
-            if (gFoundCTCSS && gFoundCTCSSCountdown_10ms == 0)
-            {
-                gFoundCTCSS = false;
-                gFoundCDCSS = false;
-                Mode        = END_OF_RX_MODE_END;
-                goto Skip;
-            }
-            break;
-
         case CODE_TYPE_DIGITAL:
         case CODE_TYPE_REVERSE_DIGITAL:
-            if (gFoundCDCSS && gFoundCDCSSCountdown_10ms == 0)
+            if ((gFoundCTCSS && gFoundCTCSSCountdown_10ms == 0) || (gFoundCDCSS && gFoundCDCSSCountdown_10ms == 0))
             {
                 gFoundCTCSS = false;
                 gFoundCDCSS = false;
@@ -544,7 +535,17 @@ void APP_StartListening(FUNCTION_Type_t function)
         gEeprom.DUAL_WATCH != DUAL_WATCH_OFF)
     {   // not scanning, dual watch is enabled
 
-        gDualWatchCountdown_10ms = dual_watch_count_after_2_10ms;
+        //gDualWatchCountdown_10ms = dual_watch_count_after_2_10ms;
+
+        const bool isMainTxDualRx =
+        (gEeprom.DUAL_WATCH != DUAL_WATCH_OFF) &&
+        (gEeprom.CROSS_BAND_RX_TX != CROSS_BAND_OFF);
+
+        // Use a short hold only for MAIN TX DUAL RX, keep legacy hold otherwise
+        gDualWatchCountdown_10ms = isMainTxDualRx
+            ? dual_watch_count_after_2_10ms / 4 // Short timer = 420 / 4 ...
+            : dual_watch_count_after_2_10ms;
+
         gScheduleDualWatch       = false;
 
         // when crossband is active only the main VFO should be used for TX
@@ -891,6 +892,12 @@ static void HandleVox(void)
 
 void APP_Update(void)
 {
+#ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
+    // Parse incoming packets on every tick so serial keys are never missed,
+    // regardless of whether the screen needs redrawing.
+    SCREENSHOT_ParseInput();
+#endif
+
 #ifdef ENABLE_VOICE
     if (gFlagPlayQueuedVoice) {
             AUDIO_PlayQueuedVoice();
@@ -1133,14 +1140,7 @@ void APP_Update(void)
             // go back to sleep
 
 #ifdef ENABLE_FEAT_F4HWN_SLEEP
-            if(gWakeUp)
-            {
-                gPowerSave_10ms = gEeprom.BATTERY_SAVE * 200; // deep sleep now indexed on BatSav
-            }
-            else
-            {
-                gPowerSave_10ms = gEeprom.BATTERY_SAVE * 10;
-            }
+            gPowerSave_10ms = gEeprom.BATTERY_SAVE * (gWakeUp ? 200 : 10); // deep sleep now indexed on BatSav
 #else
             gPowerSave_10ms = gEeprom.BATTERY_SAVE * 10;
 #endif
@@ -1165,8 +1165,21 @@ void APP_Update(void)
     }
 }
 
+void StopTransmitting(void) {
+    ProcessKey(KEY_PTT, false, false);
+    gPttIsPressed = false;
+    if (gKeyReading1 != KEY_INVALID)
+        gPttWasReleased = true;
+
+    #ifdef ENABLE_FEAT_F4HWN
+        #if defined(ENABLE_FEAT_F4HWN_CTR) || defined(ENABLE_FEAT_F4HWN_INV)
+        ST7565_ContrastAndInv();
+        #endif
+    #endif
+}
+
 // called every 10ms
-static void CheckKeys(void)
+void CheckKeys(void)
 {
 #ifdef ENABLE_DTMF_CALLING
     if(gSetting_KILLED){
@@ -1181,75 +1194,63 @@ static void CheckKeys(void)
 #endif
 
 // -------------------- PTT ------------------------
+    const bool serialConfigInProgress = SerialConfigInProgress();
+
+#ifdef ENABLE_FEAT_F4HWN
+    const bool isPressed = GPIO_IsPttPressed() && !serialConfigInProgress;
+#else
+    const bool isPressed = !GPIO_CheckBit(&GPIOC->DATA, GPIOC_PIN_PTT) && !serialConfigInProgress;
+#endif
+
 #ifdef ENABLE_FEAT_F4HWN
     if (gSetting_set_ptt_session)
     {
-        if (GPIO_IsPttPressed() && !SerialConfigInProgress() && gPttOnePushCounter == 0)
-        {   // PTT pressed
-            if (++gPttDebounceCounter >= 3)     // 30ms
-            {   // start transmitting
-                boot_counter_10ms   = 0;
+        if ((isPressed && (gPttOnePushCounter == 0 || gPttOnePushCounter == 2)) ||
+            (!isPressed && (gPttOnePushCounter == 1 || gPttOnePushCounter == 3)) ||
+            serialConfigInProgress) 
+        {
+            if (++gPttDebounceCounter >= 3 || (serialConfigInProgress && gPttOnePushCounter > 0))
+            {
                 gPttDebounceCounter = 0;
-                gPttIsPressed       = true;
-                gPttOnePushCounter = 1;
-                ProcessKey(KEY_PTT, true, false);
+                
+                if (gPttOnePushCounter == 0)
+                {   // start transmitting
+                    boot_counter_10ms   = 0;
+                    gPttIsPressed       = true;
+                    gPttOnePushCounter = 1;
+                    ProcessKey(KEY_PTT, true, false);
+                } 
+                else if (gPttOnePushCounter == 3 || serialConfigInProgress)
+                {   // stop transmitting
+                    StopTransmitting();
+                    gPttOnePushCounter = 0;
+                } 
+                else
+                    gPttOnePushCounter++;
             }
-        }
-        else if ((!GPIO_IsPttPressed() || SerialConfigInProgress()) && gPttOnePushCounter == 1)
-        {   
-            // PTT released or serial comms config in progress
-            if (++gPttDebounceCounter >= 3 || SerialConfigInProgress())     // 30ms
-            {   // stop transmitting
-                gPttOnePushCounter = 2;
-            }
-        }
-        else if (GPIO_IsPttPressed() && !SerialConfigInProgress() && gPttOnePushCounter == 2)
-        {   // PTT pressed again            
-            if (++gPttDebounceCounter >= 3 || SerialConfigInProgress())     // 30ms
-            {   // stop transmitting
-                gPttOnePushCounter = 3;
-            }
-        }
-        else if ((!GPIO_IsPttPressed() || SerialConfigInProgress()) && gPttOnePushCounter == 3)
-        {   // PTT released or serial comms config in progress
-            if (++gPttDebounceCounter >= 3 || SerialConfigInProgress())     // 30ms
-            {   // stop transmitting
-                ProcessKey(KEY_PTT, false, false);
-                gPttIsPressed = false;
-                if (gKeyReading1 != KEY_INVALID)
-                    gPttWasReleased = true;
-                gPttOnePushCounter = 0;
-                #if defined(ENABLE_FEAT_F4HWN_CTR) || defined(ENABLE_FEAT_F4HWN_INV)
-                ST7565_ContrastAndInv();
-                #endif
-            }
-        }
+        } 
         else
             gPttDebounceCounter = 0;
 
         //gDebug = gPttOnePushCounter;
-    }
-    else
+    } 
+    else 
+#endif
     {
         if (gPttIsPressed)
         {
-            if (!GPIO_IsPttPressed() || SerialConfigInProgress())
+            if (!isPressed)
             {   // PTT released or serial comms config in progress
-                if (++gPttDebounceCounter >= 3 || SerialConfigInProgress())     // 30ms
+                if (++gPttDebounceCounter >= 3 || serialConfigInProgress)   // 30ms
                 {   // stop transmitting
-                    ProcessKey(KEY_PTT, false, false);
-                    gPttIsPressed = false;
-                    if (gKeyReading1 != KEY_INVALID)
-                        gPttWasReleased = true;
-                    #if defined(ENABLE_FEAT_F4HWN_CTR) || defined(ENABLE_FEAT_F4HWN_INV)
-                    ST7565_ContrastAndInv();
-                    #endif
+                    gPttDebounceCounter = 0;
+                    StopTransmitting();
                 }
-            }
-            else
+            } 
+            else 
                 gPttDebounceCounter = 0;
         }
-        else if (GPIO_IsPttPressed() && !SerialConfigInProgress())
+        else if (isPressed)
         {   // PTT pressed
             if (++gPttDebounceCounter >= 3)     // 30ms
             {   // start transmitting
@@ -1259,38 +1260,9 @@ static void CheckKeys(void)
                 ProcessKey(KEY_PTT, true, false);
             }
         }
-        else
-            gPttDebounceCounter = 0;        
-    }
-#else
-    if (gPttIsPressed)
-    {
-        if (GPIO_CheckBit(&GPIOC->DATA, GPIOC_PIN_PTT) || SerialConfigInProgress())
-        {   // PTT released or serial comms config in progress
-            if (++gPttDebounceCounter >= 3 || SerialConfigInProgress())     // 30ms
-            {   // stop transmitting
-                ProcessKey(KEY_PTT, false, false);
-                gPttIsPressed = false;
-                if (gKeyReading1 != KEY_INVALID)
-                    gPttWasReleased = true;
-            }
-        }
         else
             gPttDebounceCounter = 0;
     }
-    else if (!GPIO_CheckBit(&GPIOC->DATA, GPIOC_PIN_PTT) && !SerialConfigInProgress())
-    {   // PTT pressed
-        if (++gPttDebounceCounter >= 3)     // 30ms
-        {   // start transmitting
-            boot_counter_10ms   = 0;
-            gPttDebounceCounter = 0;
-            gPttIsPressed       = true;
-            ProcessKey(KEY_PTT, true, false);
-        }
-    }
-    else
-        gPttDebounceCounter = 0;
-#endif
 
 // --------------------- OTHER KEYS ----------------------------
 
@@ -1364,9 +1336,9 @@ void APP_TimeSlice10ms(void)
 {
     gNextTimeslice = false;
 
-    if (gScheduleVfoSave) {
-        SETTINGS_SaveVfoIndicesFlush();
-    }
+    SETTINGS_SaveVfoIndicesFlush();
+
+    BACKLIGHT_Update();
 
     gFlashLightBlinkCounter++;
 
@@ -1392,12 +1364,18 @@ void APP_TimeSlice10ms(void)
 
     if (gCurrentFunction == FUNCTION_TRANSMIT)
     {   // transmitting
-#ifdef ENABLE_AUDIO_BAR
+#if defined(ENABLE_AUDIO_BAR) && !defined(ENABLE_FEAT_F4HWN_AUDIO_SCOPE)
         if (gSetting_mic_bar && (gFlashLightBlinkCounter % (150 / 10)) == 0) // once every 150ms
             UI_DisplayAudioBar();
 #endif
     }
 
+#ifdef ENABLE_FEAT_F4HWN_AUDIO_SCOPE
+    if (gSetting_mic_bar && (gFlashLightBlinkCounter % (20 / 10)) == 0) // once every 20ms
+        // Sample audio amplitude and refresh display during TX only (FM RX has no usable audio register)
+        UI_DisplayAudioScope();
+#endif
+
     bool gUpdateDisplayCurrent = gUpdateDisplay;
     bool gUpdateStatusCurrent  = gUpdateStatus;
 
@@ -1412,7 +1390,7 @@ void APP_TimeSlice10ms(void)
 
     #ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
     if (gUpdateDisplayCurrent || gUpdateStatusCurrent) {
-        getScreenShot(false);
+        SCREENSHOT_Update(false);
     }
     #endif
 
@@ -1525,18 +1503,16 @@ void cancelUserInputModes(void)
     if (gDTMF_InputMode || gDTMF_InputBox_Index > 0)
     {
         DTMF_clear_input_box();
-        gBeepToPlay           = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
         gRequestDisplayScreen = DISPLAY_MAIN;
         gUpdateDisplay        = true;
     }
 
     if (gWasFKeyPressed || gKeyInputCountdown > 0 || gInputBoxIndex > 0)
     {
-        gWasFKeyPressed     = false;
+        HideFKeyIcon();
+
         gInputBoxIndex      = 0;
         gKeyInputCountdown  = 0;
-        gBeepToPlay         = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
-        gUpdateStatus       = true;
         gUpdateDisplay      = true;
     }
 }
@@ -1558,18 +1534,17 @@ void APP_TimeSlice500ms(void)
         if (--gKeyInputCountdown == 0)
         {
 
-            if (IS_MR_CHANNEL(gTxVfo->CHANNEL_SAVE) && (gInputBoxIndex == 1 || gInputBoxIndex == 2))
+            if (IS_MR_CHANNEL(gTxVfo->CHANNEL_SAVE) && (gInputBoxIndex > 0 && gInputBoxIndex < 4) && (!gFmRadioMode))
             {
                 channelMoveSwitch();
 
                 if (gBeepToPlay == BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL) {
                     AUDIO_PlayBeep(gBeepToPlay);
                 }
-
-                SETTINGS_SaveVfoIndices();
             }
 
             cancelUserInputModes();
+            gHasVfoBackup = false;
         }
     }
 
@@ -1612,9 +1587,11 @@ void APP_TimeSlice500ms(void)
     }
 #endif
 
+    const int m = UI_MENU_GetCurrentMenuId();
+
     if (gBacklightCountdown_500ms > 0 && !gAskToSave && !gCssBackgroundScan
         // don't turn off backlight if user is in backlight menu option
-        && !(gScreenToDisplay == DISPLAY_MENU && (UI_MENU_GetCurrentMenuId() == MENU_ABR || UI_MENU_GetCurrentMenuId() == MENU_ABR_MAX))
+        && !(gScreenToDisplay == DISPLAY_MENU && (m == MENU_ABR || m == MENU_ABR_MAX || m == MENU_ABR_MIN))
         && --gBacklightCountdown_500ms == 0
         && gEeprom.BACKLIGHT_TIME < 61
     ) {
@@ -1732,8 +1709,10 @@ void APP_TimeSlice500ms(void)
         if (exit_menu) {
             gMenuCountdown = 0;
 
-            if (gEeprom.BACKLIGHT_TIME == 0) {
-                BACKLIGHT_TurnOff();
+            const int m = UI_MENU_GetCurrentMenuId();
+
+            if (gScreenToDisplay == DISPLAY_MENU && (m == MENU_ABR || m == MENU_ABR_MAX || m == MENU_ABR_MIN)) {
+                BACKLIGHT_TurnOn();
             }
 
             if (gInputBoxIndex > 0 || gDTMF_InputMode) {
@@ -1751,13 +1730,12 @@ void APP_TimeSlice500ms(void)
 */
             DTMF_clear_input_box();
 
-            gWasFKeyPressed  = false;
+            HideFKeyIcon();
             gInputBoxIndex   = 0;
 
             gAskToSave       = false;
             gAskToDelete     = false;
 
-            gUpdateStatus    = true;
             gUpdateDisplay   = true;
 
             GUI_DisplayType_t disp = DISPLAY_INVALID;
@@ -1936,6 +1914,7 @@ static void ProcessKey(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
 
             // cancel user input
             cancelUserInputModes();
+            gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
 
             if (gMonitor)
                 ACTION_Monitor(); //turn off the monitor
@@ -2048,8 +2027,7 @@ static void ProcessKey(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
     if (gWasFKeyPressed && (Key == KEY_PTT || Key == KEY_EXIT || Key == KEY_SIDE1 || Key == KEY_SIDE2)) { 
 #endif
         // cancel the F-key
-        gWasFKeyPressed = false;
-        gUpdateStatus   = true;
+        HideFKeyIcon();
     }
 
     if (bFlag) {
@@ -2126,18 +2104,14 @@ static void ProcessKey(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
         }
 #endif
     }
+    else if (gScreenToDisplay != DISPLAY_INVALID && (
+            (Key != KEY_SIDE1 && Key != KEY_SIDE2)
 #ifdef ENABLE_FEAT_F4HWN // For F + SIDE1 or F + SIDE2
-    else if (gWasFKeyPressed && (Key == KEY_SIDE1 || Key == KEY_SIDE2)) {
-        ProcessKeysFunctions[gScreenToDisplay](Key, bKeyPressed, bKeyHeld);
-    }
-    else if (Key != KEY_SIDE1 && Key != KEY_SIDE2 && gScreenToDisplay != DISPLAY_INVALID) {
-        ProcessKeysFunctions[gScreenToDisplay](Key, bKeyPressed, bKeyHeld);
-    }
-#else
-    else if (Key != KEY_SIDE1 && Key != KEY_SIDE2 && gScreenToDisplay != DISPLAY_INVALID) {
-        ProcessKeysFunctions[gScreenToDisplay](Key, bKeyPressed, bKeyHeld);
-    }
+            || (gWasFKeyPressed && (Key == KEY_SIDE1 || Key == KEY_SIDE2))
 #endif
+    )) {
+        ProcessKeysFunctions[gScreenToDisplay](Key, bKeyPressed, bKeyHeld);
+    }
     else if (!SCANNER_IsScanning()
 #ifdef ENABLE_AIRCOPY
             && gScreenToDisplay != DISPLAY_AIRCOPY
@@ -2170,6 +2144,7 @@ Skip:
         else
             flagSaveSettings = 1;
         gRequestSaveSettings = false;
+        gRequestSaveSquelch  = false;
         gUpdateStatus        = true;
     }
 
@@ -2192,7 +2167,7 @@ Skip:
     }
 
     if (gRequestSaveChannel > 0) { // TODO: remove the gRequestSaveChannel, why use global variable for that??
-        if ((!bKeyHeld && !bKeyPressed) || (UI_MENU_GetCurrentMenuId() != 0 && gScreenToDisplay == DISPLAY_MENU))
+        if ((!bKeyHeld && !bKeyPressed) || (UI_MENU_GetCurrentMenuId() != 0 && gScreenToDisplay == DISPLAY_MENU) || gScreenToDisplay == DISPLAY_SCANNER)
         {
             SETTINGS_SaveChannel(gTxVfo->CHANNEL_SAVE, gEeprom.TX_VFO, gTxVfo, gRequestSaveChannel);
 

App/app/breakout.c

@@ -401,50 +401,35 @@ static void OnKeyDown(uint8_t key)
     }
 }
 
-
-// Key 
-static KEY_Code_t GetKey()
-{
-    KEY_Code_t btn = KEYBOARD_Poll();
-    if (btn == KEY_INVALID && GPIO_IsPttPressed())
-    {
-        btn = KEY_PTT;
-    }
-    return btn;
-}
-
 // HandleUserInput 
 static bool HandleUserInput()
 {
-    // Store previous key state
+#ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
+    // Parse incoming packets on every tick so serial keys are never missed,
+    // regardless of whether the screen needs redrawing.
+    SCREENSHOT_ParseInput();
+#endif
+
     kbd.prev = kbd.current;
-    
-    // Get the current key
-    kbd.current = GetKey();
-    
-    // Detect valid key press continuation (same key still pressed)
-    if (kbd.current != KEY_INVALID && kbd.current == kbd.prev)
-    {
-        kbd.counter = 1;
-    }
-    else
-    {
-        kbd.counter = 0;
-    }
-    
-    // Process the key if counter indicates it should be handled
-    if (kbd.counter == 1)
+    kbd.current = KEYBOARD_GetKey();
+
+    if (kbd.current == KEY_INVALID)
+        return true;
+
+    // Movement keys: dispatch on every tick while held
+    if (kbd.current == KEY_UP   || kbd.current == KEY_DOWN ||
+        kbd.current == KEY_4    || kbd.current == KEY_0)
     {
         OnKeyDown(kbd.current);
-        
-        // Special handling for MENU key
-        if(kbd.current == KEY_MENU)
-        {
-            kbd.counter = 0;
-            SYSTEM_DelayMs(250);
-        }
+        return true;
     }
-    
+
+    // Action keys (MENU, EXIT): dispatch only on rising edge
+    if (kbd.current != kbd.prev)
+    {
+        OnKeyDown(kbd.current);
+    }
+
     return true;
 }
 
@@ -452,7 +437,6 @@ static bool HandleUserInput()
 static void Tick()
 {
     HandleUserInput();
-    HandleUserInput();
 }
 
 // APP_RunBreakout
@@ -465,6 +449,9 @@ void APP_RunBreakout(void) {
         // Init led
         BK4819_ToggleGpioOut(BK4819_GPIO6_PIN2_GREEN, false);
 
+        // Finish the brightness fade if it is in progress
+        BACKLIGHT_UpdateTickless();
+
         // Init game
         UI_DisplayClear();
         reset();
@@ -482,11 +469,6 @@ void APP_RunBreakout(void) {
                 if(swap == 0)
                 {
                     blockAnim = (blockAnim + 1) % 4;
-
-                    // For screenshot
-                    #ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
-                        getScreenShot(false);
-                    #endif
                 }
                 
                 swap = (swap + 1) % 4;
@@ -509,5 +491,12 @@ void APP_RunBreakout(void) {
 
             ST7565_BlitStatusLine();  // Blank status line
             ST7565_BlitFullScreen();
+
+            #ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
+                if(isPaused || swap == 0)
+                {
+                    SCREENSHOT_Update(false);
+                }
+            #endif
         }
 }

App/app/chFrScanner.c

@@ -37,6 +37,15 @@ uint8_t             initialCROSS_BAND_RX_TX;
 static void NextFreqChannel(void);
 static void NextMemChannel(void);
 
+#if defined(ENABLE_FEAT_F4HWN_RESUME_STATE) || defined(ENABLE_SCAN_RANGES)
+    void CHFRSCANNER_ScanRange(void) {
+        gScanRangeStart = gScanRangeStart ? 0 : gTxVfo->pRX->Frequency;
+        gScanRangeStop = gEeprom.VfoInfo[!gEeprom.TX_VFO].freq_config_RX.Frequency;
+        if(gScanRangeStart > gScanRangeStop)
+            SWAP(gScanRangeStart, gScanRangeStop);
+    }
+#endif
+
 void CHFRSCANNER_Start(const bool storeBackupSettings, const int8_t scan_direction)
 {
     if (storeBackupSettings) {
@@ -55,7 +64,7 @@ void CHFRSCANNER_Start(const bool storeBackupSettings, const int8_t scan_directi
     {   
 
         if(!RADIO_CheckValidList(gEeprom.SCAN_LIST_DEFAULT)) {
-            RADIO_NextValidList();
+            RADIO_NextValidList(1);
         }
 
         // channel mode

App/app/chFrScanner.h

@@ -20,6 +20,10 @@ void CHFRSCANNER_Stop(void);
 void CHFRSCANNER_Start(const bool storeBackupSettings, const int8_t scan_direction);
 void CHFRSCANNER_ContinueScanning(void);
 
+#if defined(ENABLE_FEAT_F4HWN_RESUME_STATE) || defined(ENABLE_SCAN_RANGES)
+    void CHFRSCANNER_ScanRange(void);
+#endif
+
 #ifdef ENABLE_FEAT_F4HWN
     extern uint32_t lastFoundFrqOrChan;
     extern uint32_t lastFoundFrqOrChanOld;

App/app/common.c

@@ -3,6 +3,7 @@
 #include "functions.h"
 #include "misc.h"
 #include "settings.h"
+#include "ui/inputbox.h"
 #include "ui/ui.h"
 
 void COMMON_KeypadLockToggle() 
@@ -29,6 +30,11 @@ void COMMON_SwitchVFOs()
 #endif
     gEeprom.TX_VFO ^= 1;
 
+    if (gInputBoxIndex > 0) {
+        gInputBoxIndex = 0;
+        gHasVfoBackup = false;
+    }
+
     if (gEeprom.CROSS_BAND_RX_TX != CROSS_BAND_OFF)
         gEeprom.CROSS_BAND_RX_TX = gEeprom.TX_VFO + 1;
     if (gEeprom.DUAL_WATCH != DUAL_WATCH_OFF)
@@ -49,6 +55,11 @@ void COMMON_SwitchVFOMode()
     if (gEeprom.VFO_OPEN)
 #endif
     {
+        if (gInputBoxIndex > 0) {
+            gInputBoxIndex = 0;
+            gHasVfoBackup = false;
+        }
+
         if (IS_MR_CHANNEL(gTxVfo->CHANNEL_SAVE))
         {   // swap to frequency mode
             gEeprom.ScreenChannel[gEeprom.TX_VFO] = gEeprom.FreqChannel[gEeprom.TX_VFO];

App/app/flashlight.c

@@ -51,20 +51,26 @@ static inline void Flashlight_Toggle(){ GPIO_TogglePin(GPIO_PIN_FLASHLIGHT); }
 
     void ACTION_FlashLight(void)
     {
-        switch (gFlashLightState) {
-            case FLASHLIGHT_OFF:
-                gFlashLightState++;
-                Flashlight_TurnOn();
-                break;
-            case FLASHLIGHT_ON:
-            case FLASHLIGHT_BLINK:
-                gFlashLightState++;
-                break;
-            case FLASHLIGHT_SOS:
-            default:
-                gFlashLightState = 0;
-                Flashlight_TurnOff();
+        // switch (gFlashLightState) {
+        //     case FLASHLIGHT_OFF:
+        //         Flashlight_TurnOn();
+        //         break;
+        //     case FLASHLIGHT_ON:
+        //     case FLASHLIGHT_BLINK:
+        //         break;
+        //     case FLASHLIGHT_SOS:
+        //     default:
+        //         Flashlight_TurnOff();
+        // }
+
+        if(gFlashLightState == FLASHLIGHT_OFF) {
+            Flashlight_TurnOn();
         }
+        else if (gFlashLightState == FLASHLIGHT_SOS) {
+            Flashlight_TurnOff();
+        }
+
+        gFlashLightState = (gFlashLightState + 1) % 4;
     }
 #else
     void ACTION_FlashLight(void)

App/app/fm.c

@@ -129,6 +129,18 @@ void FM_EraseChannels(void)
     memset(gFM_Channels, 0xFF, sizeof(gFM_Channels));
 }
 
+uint16_t FM_WrapFrequency(uint16_t Frequency) {
+    const uint16_t freqLoLimit = BK1080_GetFreqLoLimit(gEeprom.FM_Band);
+    const uint16_t freqHiLimit = BK1080_GetFreqHiLimit(gEeprom.FM_Band);
+
+    if (Frequency < freqLoLimit)
+        return freqHiLimit;
+    else if (Frequency > freqHiLimit)
+        return freqLoLimit;
+
+    return Frequency;
+}
+
 void FM_Tune(uint16_t Frequency, int8_t Step, bool bFlag)
 {
     AUDIO_AudioPathOff();
@@ -145,10 +157,7 @@ void FM_Tune(uint16_t Frequency, int8_t Step, bool bFlag)
 
     if (!bFlag) {
         Frequency += Step;
-        if (Frequency < BK1080_GetFreqLoLimit(gEeprom.FM_Band))
-            Frequency = BK1080_GetFreqHiLimit(gEeprom.FM_Band);
-        else if (Frequency > BK1080_GetFreqHiLimit(gEeprom.FM_Band))
-            Frequency = BK1080_GetFreqLoLimit(gEeprom.FM_Band);
+        Frequency = FM_WrapFrequency(Frequency);
 
         gEeprom.FM_FrequencyPlaying = Frequency;
     }
@@ -182,65 +191,45 @@ void FM_PlayAndUpdate(void)
 
 int FM_CheckFrequencyLock(uint16_t Frequency, uint16_t LowerLimit)
 {
-    int ret = -1;
-
-    const uint16_t Test2 = BK1080_ReadRegister(BK1080_REG_07);
-
-    // This is supposed to be a signed value, but above function is unsigned
+    const uint16_t Test2     = BK1080_ReadRegister(BK1080_REG_07);
     const uint16_t Deviation = BK1080_REG_07_GET_FREQD(Test2);
 
-    if (BK1080_REG_07_GET_SNR(Test2) <= 2) {
-        BK1080_FrequencyDeviation = Deviation;
-        BK1080_BaseFrequency      = Frequency;
+    // Helper macro to update globals and return
+    #define RETURN(val) \
+        do { \
+            BK1080_FrequencyDeviation = Deviation; \
+            BK1080_BaseFrequency      = Frequency; \
+            return (val); \
+        } while (0)
 
-        return ret;
-    }
+    if (BK1080_REG_07_GET_SNR(Test2) <= 2)
+        RETURN(-1);
 
     const uint16_t Status = BK1080_ReadRegister(BK1080_REG_10);
+    if ((Status & BK1080_REG_10_MASK_AFCRL) != BK1080_REG_10_AFCRL_NOT_RAILED ||
+        BK1080_REG_10_GET_RSSI(Status) < 10)
+        RETURN(-1);
 
-    if ((Status & BK1080_REG_10_MASK_AFCRL) != BK1080_REG_10_AFCRL_NOT_RAILED || BK1080_REG_10_GET_RSSI(Status) < 10) {
-        BK1080_FrequencyDeviation = Deviation;
-        BK1080_BaseFrequency      = Frequency;
+    if (Deviation >= 280 && Deviation <= 3815)
+        RETURN(-1);
 
-        return ret;
-    }
-
-    //if (Deviation > -281 && Deviation < 280)
-    if (Deviation >= 280 && Deviation <= 3815) {
-        BK1080_FrequencyDeviation = Deviation;
-        BK1080_BaseFrequency      = Frequency;
-
-        return ret;
-    }
-
-    // not BLE(less than or equal)
+    // Scanning upward: previous deviation was negative (bit 11 set) or near zero
     if (Frequency > LowerLimit && (Frequency - BK1080_BaseFrequency) == 1) {
-        if (BK1080_FrequencyDeviation & 0x800 || (BK1080_FrequencyDeviation < 20))
-        {
-            BK1080_FrequencyDeviation = Deviation;
-            BK1080_BaseFrequency      = Frequency;
-
-            return ret;
-        }
+        if (BK1080_FrequencyDeviation & 0x800 || BK1080_FrequencyDeviation < 20)
+            RETURN(-1);
     }
 
-    // not BLT(less than)
-
+    // Scanning downward: previous deviation was positive or saturated high
     if (Frequency >= LowerLimit && (BK1080_BaseFrequency - Frequency) == 1) {
-        if ((BK1080_FrequencyDeviation & 0x800) == 0 || (BK1080_FrequencyDeviation > 4075))
-        {
-            BK1080_FrequencyDeviation = Deviation;
-            BK1080_BaseFrequency      = Frequency;
-
-            return ret;
-        }
+        if ((BK1080_FrequencyDeviation & 0x800) == 0 || BK1080_FrequencyDeviation > 4075)
+            RETURN(-1);
     }
 
-    ret = 0;
+    #undef RETURN
+
     BK1080_FrequencyDeviation = Deviation;
     BK1080_BaseFrequency      = Frequency;
-
-    return ret;
+    return 0;
 }
 
 static void Key_DIGITS(KEY_Code_t Key, uint8_t state)
@@ -268,6 +257,7 @@ static void Key_DIGITS(KEY_Code_t Key, uint8_t state)
         }
 
         INPUTBOX_Append(Key);
+        gKeyInputCountdown = key_input_timeout_500ms;
 
         gRequestDisplayScreen = DISPLAY_FM;
 
@@ -283,6 +273,8 @@ static void Key_DIGITS(KEY_Code_t Key, uint8_t state)
                 uint32_t Frequency;
 
                 gInputBoxIndex = 0;
+                gKeyInputCountdown = 1;
+
                 Frequency = StrToUL(INPUTBOX_GetAscii());
 
                 if (Frequency < BK1080_GetFreqLoLimit(gEeprom.FM_Band) || BK1080_GetFreqHiLimit(gEeprom.FM_Band) < Frequency) {
@@ -305,6 +297,8 @@ static void Key_DIGITS(KEY_Code_t Key, uint8_t state)
             uint8_t Channel;
 
             gInputBoxIndex = 0;
+            gKeyInputCountdown = 1;
+            
             Channel = ((gInputBox[0] * 10) + gInputBox[1]) - 1;
 
             if (State == STATE_MR_MODE) {
@@ -347,8 +341,7 @@ static void Key_FUNC(KEY_Code_t Key, uint8_t state)
         bool autoScan = gWasFKeyPressed || (state == BUTTON_EVENT_HELD);
 
         gBeepToPlay           = BEEP_1KHZ_60MS_OPTIONAL;
-        gWasFKeyPressed       = false;
-        gUpdateStatus         = true;
+        HideFKeyIcon();
         gRequestDisplayScreen = DISPLAY_FM;
 
         switch (Key) {
@@ -377,6 +370,14 @@ static void Key_FUNC(KEY_Code_t Key, uint8_t state)
                     gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
                 break;
 
+            case KEY_8:
+                ACTION_BackLightOnDemand();
+                break;
+
+            case KEY_9:
+                ACTION_BackLight();
+                break;
+
             case KEY_STAR:
                 ACTION_Scan(autoScan);
                 break;
@@ -407,6 +408,7 @@ static void Key_EXIT(uint8_t state)
         }
         else {
             gInputBox[--gInputBoxIndex] = 10;
+            gKeyInputCountdown = key_input_timeout_500ms;
 
             if (gInputBoxIndex) {
                 if (gInputBoxIndex != 1) {
@@ -438,14 +440,25 @@ static void Key_EXIT(uint8_t state)
 
 static void Key_MENU(uint8_t state)
 {
-    if (state != BUTTON_EVENT_SHORT)
+    if (state == BUTTON_EVENT_HELD) {
+        ACTION_Handle(KEY_MENU, true, true);
         return;
-
+    }
+    else if (state != BUTTON_EVENT_SHORT) {
+        return;
+    }
 
     gRequestDisplayScreen = DISPLAY_FM;
     gBeepToPlay           = BEEP_1KHZ_60MS_OPTIONAL;
 
+    HideFKeyIcon();
+
     if (gFM_ScanState == FM_SCAN_OFF) {
+        if (gInputBoxIndex) {
+            gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
+            return;
+        }
+
         if (!gEeprom.FM_IsMrMode) {
             if (gAskToSave) {
                 gFM_Channels[gFM_ChannelPosition] = gEeprom.FM_FrequencyPlaying;
@@ -482,6 +495,8 @@ static void Key_MENU(uint8_t state)
 
 static void Key_UP_DOWN(uint8_t state, int8_t Step)
 {
+    HideFKeyIcon();
+
     if (state == BUTTON_EVENT_PRESSED) {
         if (gInputBoxIndex) {
             gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
@@ -493,6 +508,10 @@ static void Key_UP_DOWN(uint8_t state, int8_t Step)
         return;
     }
 
+    if (!gEeprom.SET_NAV) {
+        Step = -Step;
+    }
+
     if (gAskToSave) {
         gRequestDisplayScreen = DISPLAY_FM;
         gFM_ChannelPosition   = NUMBER_AddWithWraparound(gFM_ChannelPosition, Step, 0, FM_CHANNELS_MAX - 1);
@@ -521,10 +540,7 @@ static void Key_UP_DOWN(uint8_t state, int8_t Step)
     else {
         uint16_t Frequency = gEeprom.FM_SelectedFrequency + Step;
 
-        if (Frequency < BK1080_GetFreqLoLimit(gEeprom.FM_Band))
-            Frequency = BK1080_GetFreqHiLimit(gEeprom.FM_Band);
-        else if (Frequency > BK1080_GetFreqHiLimit(gEeprom.FM_Band))
-            Frequency = BK1080_GetFreqLoLimit(gEeprom.FM_Band);
+        Frequency = FM_WrapFrequency(Frequency);
 
         gEeprom.FM_FrequencyPlaying  = Frequency;
         gEeprom.FM_SelectedFrequency = gEeprom.FM_FrequencyPlaying;
@@ -553,16 +569,8 @@ void FM_ProcessKeys(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
             Key_MENU(state);
             break;
         case KEY_UP:
-            if(gEeprom.SET_NAV == 0)
-                Key_UP_DOWN(state, -1);
-            else
-                Key_UP_DOWN(state, 1);
-            break;
         case KEY_DOWN:
-            if(gEeprom.SET_NAV == 0)
-                Key_UP_DOWN(state, 1);
-            else
-                Key_UP_DOWN(state, -1);
+            Key_UP_DOWN(state, Key == KEY_UP ? 1 : -1);
             break;
         case KEY_EXIT:
             Key_EXIT(state);
@@ -573,9 +581,14 @@ void FM_ProcessKeys(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
         case KEY_PTT:
             GENERIC_Key_PTT(bKeyPressed);
             break;
-        default:
-            if (!bKeyHeld && bKeyPressed)
+        case KEY_SIDE1:
+        case KEY_SIDE2:
+            if (state != BUTTON_EVENT_PRESSED) {
                 gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
+                HideFKeyIcon();
+            }
+            break;
+        default:
             break;
     }
 }

App/app/generic.c

@@ -39,7 +39,7 @@
 
 void GENERIC_Key_F(bool bKeyPressed, bool bKeyHeld)
 {
-    if (gInputBoxIndex > 0) {
+    if (gInputBoxIndex > 0 || gScreenToDisplay == DISPLAY_MENU) {
         if (!bKeyHeld && bKeyPressed) // short pressed
             gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
         return;

App/app/main.c

@@ -47,6 +47,31 @@
 #include "ui/ui.h"
 #include <stdlib.h>
 
+// Full VFO backup for restore on EXIT
+static VFO_Info_t gVfoBackup;
+static uint16_t   gScreenChannelBackup = 0;
+static uint16_t   gFreqChannelBackup = 0;
+
+static void VFO_RestoreBackup(void) {
+    if (gHasVfoBackup) {
+        const uint8_t Vfo = gEeprom.TX_VFO;
+
+        // Restore indices
+        gEeprom.ScreenChannel[Vfo] = gScreenChannelBackup;
+        gEeprom.FreqChannel[Vfo] = gFreqChannelBackup;
+
+        // Restore full VFO
+        memcpy(gTxVfo, &gVfoBackup, sizeof(VFO_Info_t));
+
+        // Save and apply
+        SETTINGS_SaveVfoIndices();
+        RADIO_ConfigureSquelchAndOutputPower(gTxVfo);
+        RADIO_SetupRegisters(true);
+
+        gHasVfoBackup = false;
+    }
+}
+
 static void toggle_chan_scanlist(void)
 {   // toggle the selected channels scanlist setting
 
@@ -55,10 +80,7 @@ static void toggle_chan_scanlist(void)
 
     if(!IS_MR_CHANNEL(gTxVfo->CHANNEL_SAVE)) {
 #ifdef ENABLE_SCAN_RANGES
-        gScanRangeStart = gScanRangeStart ? 0 : gTxVfo->pRX->Frequency;
-        gScanRangeStop = gEeprom.VfoInfo[!gEeprom.TX_VFO].freq_config_RX.Frequency;
-        if(gScanRangeStart > gScanRangeStop)
-            SWAP(gScanRangeStart, gScanRangeStop);
+        CHFRSCANNER_ScanRange();
 #endif
         return;
     }
@@ -69,20 +91,22 @@ static void toggle_chan_scanlist(void)
     if(att->exclude == true)
     {
         att->exclude = false;
-        return;
+        MR_SaveChannelAttributesToFlash(gTxVfo->CHANNEL_SAVE, att);
+    } 
+    else 
+    {
+        uint8_t scanlist = gTxVfo->SCANLIST_PARTICIPATION;
+
+        scanlist++;
+
+        if (scanlist > MR_CHANNELS_LIST + 1)
+            scanlist = 0;
+
+        gTxVfo->SCANLIST_PARTICIPATION = scanlist;
+
+        SETTINGS_UpdateChannel(gTxVfo->CHANNEL_SAVE, gTxVfo, true, true, true);
     }
 
-    uint8_t scanlist = gTxVfo->SCANLIST_PARTICIPATION;
-
-    scanlist++;
-
-    if (scanlist > MR_CHANNELS_LIST + 1)
-        scanlist = 0;
-
-    gTxVfo->SCANLIST_PARTICIPATION = scanlist;
-
-    SETTINGS_UpdateChannel(gTxVfo->CHANNEL_SAVE, gTxVfo, true, true, true);
-
     gVfoConfigureMode = VFO_CONFIGURE;
     gFlagResetVfos    = true;
 }
@@ -91,16 +115,14 @@ static void processFKeyFunction(const KEY_Code_t Key, const bool beep)
 {
     uint8_t Vfo = gEeprom.TX_VFO;
 
-#ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
-    if(gEeprom.MENU_LOCK == true) {
-        if(Key == 2) { // Enable A/B only
-            gVfoConfigureMode     = VFO_CONFIGURE;
-            COMMON_SwitchVFOs();
-            if (beep)
-                gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
-        }
+    if (beep)
+        gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
 
-        return; // prevent F function if MENU LOCK is true
+#ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
+    if(gEeprom.MENU_LOCK == true && Key != 2) {
+        HideFKeyIcon();
+
+        return;
     }
 #endif
 
@@ -108,8 +130,6 @@ static void processFKeyFunction(const KEY_Code_t Key, const bool beep)
         gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
         return;
     }
-    
-    gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
 
     switch (Key) {
         case KEY_0:
@@ -120,9 +140,7 @@ static void processFKeyFunction(const KEY_Code_t Key, const bool beep)
 
         case KEY_1:
             if (!IS_FREQ_CHANNEL(gTxVfo->CHANNEL_SAVE)) {
-                gWasFKeyPressed = false;
-                gUpdateStatus   = true;
-                gBeepToPlay     = BEEP_1KHZ_60MS_OPTIONAL;
+                HideFKeyIcon();
 
 #ifdef ENABLE_COPY_CHAN_TO_VFO
                 if (!gEeprom.VFO_OPEN || gCssBackgroundScan) {
@@ -186,9 +204,6 @@ static void processFKeyFunction(const KEY_Code_t Key, const bool beep)
 
             gRequestDisplayScreen      = DISPLAY_MAIN;
 
-            if (beep)
-                gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
-
             break;
 
         case KEY_2:
@@ -196,8 +211,6 @@ static void processFKeyFunction(const KEY_Code_t Key, const bool beep)
                 gVfoConfigureMode     = VFO_CONFIGURE;
             #endif
             COMMON_SwitchVFOs();
-            if (beep)
-                gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
             break;
 
         case KEY_3:
@@ -205,26 +218,21 @@ static void processFKeyFunction(const KEY_Code_t Key, const bool beep)
                 gVfoConfigureMode     = VFO_CONFIGURE;
             #endif
             COMMON_SwitchVFOMode();
-            if (beep)
-                gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
 
             break;
 
         case KEY_4:
-            gWasFKeyPressed          = false;
+            HideFKeyIcon();
 
             gBackup_CROSS_BAND_RX_TX  = gEeprom.CROSS_BAND_RX_TX;
-            gEeprom.CROSS_BAND_RX_TX = CROSS_BAND_OFF;
-            gUpdateStatus            = true;        
-            if (beep)
-                gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
+            gEeprom.CROSS_BAND_RX_TX = CROSS_BAND_OFF;     
 
             SCANNER_Start(false);
             gRequestDisplayScreen = DISPLAY_SCANNER;
             break;
 
         case KEY_5:
-            if(beep) {
+            if(!beep) {
 #ifdef ENABLE_NOAA
                 if (!IS_NOAA_CHANNEL(gTxVfo->CHANNEL_SAVE)) {
                     gEeprom.ScreenChannel[Vfo] = gEeprom.NoaaChannel[gEeprom.TX_VFO];
@@ -285,47 +293,50 @@ static void processFKeyFunction(const KEY_Code_t Key, const bool beep)
 
 #ifdef ENABLE_FEAT_F4HWN // Set Squelch F + UP or Down and Step F + SIDE1 or F + SIDE2
         case KEY_UP:
-            gEeprom.SQUELCH_LEVEL = (gEeprom.SQUELCH_LEVEL < 9) ? gEeprom.SQUELCH_LEVEL + 1: 9;
-            gVfoConfigureMode     = VFO_CONFIGURE;
-            gWasFKeyPressed = false;
-            break;
         case KEY_DOWN:
-            gEeprom.SQUELCH_LEVEL = (gEeprom.SQUELCH_LEVEL > 0) ? gEeprom.SQUELCH_LEVEL - 1: 0;
-            gVfoConfigureMode     = VFO_CONFIGURE;
-            gWasFKeyPressed = false;
-            break;
+            {
+                bool isKeyUp = (Key == KEY_UP);
 
+                if (gScanStateDir != SCAN_OFF) {
+                    RADIO_NextValidList(isKeyUp ? 1 : -1);
+                } else {
+                    // Adjust squelch: UP increments, DOWN decrements
+                    if (isKeyUp) {
+                        gEeprom.SQUELCH_LEVEL = (gEeprom.SQUELCH_LEVEL < 9) ? gEeprom.SQUELCH_LEVEL + 1 : 9;
+                    } else {
+                        gEeprom.SQUELCH_LEVEL = (gEeprom.SQUELCH_LEVEL > 0) ? gEeprom.SQUELCH_LEVEL - 1 : 0;
+                    }
+                    gVfoConfigureMode = VFO_CONFIGURE;
+                }
+
+                gWasFKeyPressed = false;
+
+                break;
+            }
         case KEY_SIDE1:
-            uint8_t a = FREQUENCY_GetSortedIdxFromStepIdx(gTxVfo->STEP_SETTING);
-            if (a < STEP_N_ELEM - 1)
-            {
-                gTxVfo->STEP_SETTING = FREQUENCY_GetStepIdxFromSortedIdx(a + 1);
-            }
-            if (IS_FREQ_CHANNEL(gTxVfo->CHANNEL_SAVE))
-            {
-                gRequestSaveChannel = 1;
-            }
-            gVfoConfigureMode     = VFO_CONFIGURE;
-            gWasFKeyPressed = false;
-            break;
         case KEY_SIDE2:
-            uint8_t b = FREQUENCY_GetSortedIdxFromStepIdx(gTxVfo->STEP_SETTING);
-            if (b > 0)
             {
-                gTxVfo->STEP_SETTING = FREQUENCY_GetStepIdxFromSortedIdx(b - 1);
+                bool isKeySide1 = (Key == KEY_SIDE1);
+                uint8_t idx = FREQUENCY_GetSortedIdxFromStepIdx(gTxVfo->STEP_SETTING);
+
+                if ((isKeySide1 && idx < STEP_N_ELEM - 1) || (!isKeySide1 && idx > 0)) 
+                {
+                    gTxVfo->STEP_SETTING = FREQUENCY_GetStepIdxFromSortedIdx(idx + (isKeySide1 ? 1 : -1));
+                    
+                    if (IS_FREQ_CHANNEL(gTxVfo->CHANNEL_SAVE)) {
+                        gRequestSaveChannel = 1;
+                    }
+                    gVfoConfigureMode = VFO_CONFIGURE;
+                }
+                
+                gWasFKeyPressed = false;
+
+                break;
             }
-            if (IS_FREQ_CHANNEL(gTxVfo->CHANNEL_SAVE))
-            {
-                gRequestSaveChannel = 1;
-            }
-            gVfoConfigureMode     = VFO_CONFIGURE;
-            gWasFKeyPressed = false;
-            break;
 #endif
 
         default:
-            gUpdateStatus   = true;
-            gWasFKeyPressed = false;
+            HideFKeyIcon();
 
             if (beep)
                 gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
@@ -362,6 +373,8 @@ void channelMove(uint16_t Channel)
 #endif
 
     RADIO_ConfigureChannel(gEeprom.TX_VFO, gVfoConfigureMode);
+
+    SETTINGS_SaveVfoIndices();
     
     return;
 }
@@ -396,11 +409,6 @@ void channelMoveSwitch(void) {
         if (gInputBoxIndex == 4) {
             gInputBoxIndex = 0;
             gKeyInputCountdown = 1;
-
-            channelMove(Channel - 1);
-            SETTINGS_SaveVfoIndices();
-            
-            return;
         }
 
         channelMove(Channel - 1);
@@ -418,10 +426,9 @@ static void MAIN_Key_DIGITS(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
                     gRequestDisplayScreen = DISPLAY_MAIN;
                 }
 
-                gWasFKeyPressed = false;
-                gUpdateStatus   = true;
+                HideFKeyIcon();
 
-                processFKeyFunction(Key, false);
+                processFKeyFunction(Key, true);
             }
         }
         return;
@@ -480,17 +487,14 @@ static void MAIN_Key_DIGITS(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
             /* 01 .. MR_CHANNELS_LIST */
             if (value <= MR_CHANNELS_LIST)
             {
-                if (RADIO_CheckValidList(value))
-                {
-                    /* Requested scan list is valid */
-                    gEeprom.SCAN_LIST_DEFAULT = value;
-                }
-                else
+                gEeprom.SCAN_LIST_DEFAULT = value;
+
+                if (!RADIO_CheckValidList(value))
                 {
                     /* Requested scan list is empty or invalid:
-                       jump to the next valid scan list */
-                    gEeprom.SCAN_LIST_DEFAULT = value;
-                    RADIO_NextValidList();
+                        jump to the next valid scan list */
+                    gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
+                    RADIO_NextValidList(1);
                 }
 
             #ifdef ENABLE_FEAT_F4HWN_RESUME_STATE
@@ -498,13 +502,19 @@ static void MAIN_Key_DIGITS(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
             #endif
             }
 
-            gInputBoxIndex = 0;
-
-            gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
             return;
         }
 
         const uint8_t Vfo = gEeprom.TX_VFO;
+
+        // Save full VFO state BEFORE first digit
+        if (gInputBoxIndex == 0 && IS_FREQ_CHANNEL(gTxVfo->CHANNEL_SAVE)) {
+            memcpy(&gVfoBackup, gTxVfo, sizeof(VFO_Info_t));
+            gScreenChannelBackup = gEeprom.ScreenChannel[Vfo];
+            gFreqChannelBackup = gEeprom.FreqChannel[Vfo];
+            gHasVfoBackup = true;
+        }
+
         INPUTBOX_Append(Key);
         gKeyInputCountdown = key_input_timeout_500ms;
 
@@ -542,7 +552,13 @@ static void MAIN_Key_DIGITS(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
                 return;
             }
             
-            gKeyInputCountdown = (gInputBoxIndex == totalDigits) ? (key_input_timeout_500ms / 16) : (key_input_timeout_500ms / 3);
+            gKeyInputCountdown = (gInputBoxIndex >= totalDigits) ? (key_input_timeout_500ms / 16) : (key_input_timeout_500ms / 3);
+
+            if (gInputBoxIndex > totalDigits) {
+                gInputBoxIndex =  totalDigits;
+
+                return;
+            }
 
             const char *inputStr = INPUTBOX_GetAscii();
             uint8_t inputLength = gInputBoxIndex;
@@ -611,6 +627,7 @@ static void MAIN_Key_DIGITS(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
                 }
 
                 gInputBoxIndex = 0;
+                gHasVfoBackup = false;
 
                 uint8_t Channel = (gInputBox[0] * 10) + gInputBox[1];
                 if (Channel >= 1 && Channel <= ARRAY_SIZE(NoaaFrequencyTable)) {
@@ -632,8 +649,13 @@ static void MAIN_Key_DIGITS(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
         return;
     }
 
-    gWasFKeyPressed = false;
-    gUpdateStatus   = true;
+    HideFKeyIcon();
+
+    #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
+        if(gEeprom.MENU_LOCK == true && Key != 2) {
+            return;
+        }
+    #endif
 
     if(Key == 8)
     {
@@ -648,79 +670,80 @@ static void MAIN_Key_DIGITS(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
     #ifdef ENABLE_FEAT_F4HWN_GAME
     else if(Key == 7)
     {
-        #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
-            if(gEeprom.MENU_LOCK == true) {
-                return;
-            }
-        #endif
         APP_RunBreakout();
         return;
     }
     #endif
 
-    processFKeyFunction(Key, true);
+    processFKeyFunction(Key, false);
 }
 
 static void MAIN_Key_EXIT(bool bKeyPressed, bool bKeyHeld)
 {
     if (!bKeyHeld && bKeyPressed) { // exit key pressed
-        gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
+        gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;  // beep when key is pressed
+        return;                                 // don't use the key till it's released
+    }
 
-#ifdef ENABLE_DTMF_CALLING
-        if (gDTMF_CallState != DTMF_CALL_STATE_NONE && gCurrentFunction != FUNCTION_TRANSMIT)
-        {   // clear CALL mode being displayed
-            gDTMF_CallState = DTMF_CALL_STATE_NONE;
-            gUpdateDisplay  = true;
-            return;
-        }
-#endif
-
-#ifdef ENABLE_FMRADIO
-        if (!gFmRadioMode)
-#endif
-        {
-            if (gScanStateDir == SCAN_OFF) {
-                if (gInputBoxIndex == 0)
-                    return;
-                gInputBox[--gInputBoxIndex] = 10;
-
-                gKeyInputCountdown = key_input_timeout_500ms;
-
-#ifdef ENABLE_VOICE
-                if (gInputBoxIndex == 0)
-                    gAnotherVoiceID = VOICE_ID_CANCEL;
-#endif
-            }
-            else {
-                gScanKeepResult = false;
-                CHFRSCANNER_Stop();
-
-#ifdef ENABLE_VOICE
-                gAnotherVoiceID = VOICE_ID_SCANNING_STOP;
-#endif
-            }
+    if (bKeyHeld) { // exit key held down
+        if (bKeyPressed) {
+            // Restore full VFO state on long press EXIT
+            VFO_RestoreBackup();
 
             gRequestDisplayScreen = DISPLAY_MAIN;
-            return;
         }
 
-#ifdef ENABLE_FMRADIO
-        ACTION_FM();
-#endif
         return;
     }
 
-    if (bKeyHeld && bKeyPressed) { // exit key held down
-        if (gInputBoxIndex > 0 || gDTMF_InputBox_Index > 0 || gDTMF_InputMode)
-        {   // cancel key input mode (channel/frequency entry)
-            gDTMF_InputMode       = false;
-            gDTMF_InputBox_Index  = 0;
-            memset(gDTMF_String, 0, sizeof(gDTMF_String));
-            gInputBoxIndex        = 0;
-            gRequestDisplayScreen = DISPLAY_MAIN;
-            gBeepToPlay           = BEEP_1KHZ_60MS_OPTIONAL;
-        }
+#ifdef ENABLE_DTMF_CALLING
+    if (gDTMF_CallState != DTMF_CALL_STATE_NONE && gCurrentFunction != FUNCTION_TRANSMIT)
+    {   // clear CALL mode being displayed
+        gDTMF_CallState = DTMF_CALL_STATE_NONE;
+        gUpdateDisplay  = true;
+        return;
     }
+#endif
+
+#ifdef ENABLE_FMRADIO
+    if (!gFmRadioMode)
+#endif
+    {
+        if (gScanStateDir == SCAN_OFF) {
+            if (gInputBoxIndex == 0)
+                return;
+            gInputBox[--gInputBoxIndex] = 10;
+
+            // Restore full VFO state when back to 0
+            if (gInputBoxIndex == 0)
+                VFO_RestoreBackup();
+
+            gKeyInputCountdown = key_input_timeout_500ms;
+            channelMoveSwitch();
+
+#ifdef ENABLE_VOICE
+            if (gInputBoxIndex == 0)
+                gAnotherVoiceID = VOICE_ID_CANCEL;
+#endif
+        }
+        else {
+            gScanKeepResult = false;
+            gInputBoxIndex = 0;
+            CHFRSCANNER_Stop();
+
+#ifdef ENABLE_VOICE
+            gAnotherVoiceID = VOICE_ID_SCANNING_STOP;
+#endif
+        }
+
+        gRequestDisplayScreen = DISPLAY_MAIN;
+        return;
+    }
+
+#ifdef ENABLE_FMRADIO
+    ACTION_FM();
+#endif
+    return;
 }
 
 static void MAIN_Key_MENU(bool bKeyPressed, bool bKeyHeld)
@@ -762,7 +785,6 @@ static void MAIN_Key_MENU(bool bKeyPressed, bool bKeyHeld)
                     gRequestDisplayScreen = DISPLAY_MAIN;
                 }
 
-                gWasFKeyPressed = false;
                 gUpdateStatus   = true;
 
                 ACTION_Handle(KEY_MENU, bKeyPressed, bKeyHeld);
@@ -773,6 +795,9 @@ static void MAIN_Key_MENU(bool bKeyPressed, bool bKeyHeld)
     }
 
     if (!bKeyPressed && !gDTMF_InputMode) { // menu key released
+        gKeyInputCountdown = 1;
+        channelMoveSwitch();
+
         const bool bFlag = !gInputBoxIndex;
         gInputBoxIndex   = 0;
 
@@ -783,7 +808,11 @@ static void MAIN_Key_MENU(bool bKeyPressed, bool bKeyHeld)
             }
 
             #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
-            if(gEeprom.MENU_LOCK == false) {
+                if(gEeprom.MENU_LOCK == true) {
+                    HideFKeyIcon();
+
+                    return;
+                }
             #endif
 
             gFlagRefreshSetting = true;
@@ -791,10 +820,6 @@ static void MAIN_Key_MENU(bool bKeyPressed, bool bKeyHeld)
             #ifdef ENABLE_VOICE
                 gAnotherVoiceID   = VOICE_ID_MENU;
             #endif
-
-            #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
-            }
-            #endif
         }
         else {
             gRequestDisplayScreen = DISPLAY_MAIN;
@@ -804,13 +829,6 @@ static void MAIN_Key_MENU(bool bKeyPressed, bool bKeyHeld)
 
 static void MAIN_Key_STAR(bool bKeyPressed, bool bKeyHeld)
 {
-
-#ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
-    if(gEeprom.MENU_LOCK == true) {
-        return; // prevent F function if MENU LOCK is true
-    }
-#endif
-
     if (gCurrentFunction == FUNCTION_TRANSMIT)
         return;
     
@@ -820,6 +838,19 @@ static void MAIN_Key_STAR(bool bKeyPressed, bool bKeyHeld)
         return;
     }
 
+    if (!bKeyHeld && bKeyPressed) { // star key pressed
+        gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;  // beep when key is pressed
+        return;                                 // don't use the key till it's released
+    }
+
+    #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
+        if(gEeprom.MENU_LOCK == true) {
+            HideFKeyIcon();
+
+            return; // prevent F function if MENU LOCK is true
+        }
+    #endif
+
     if (bKeyHeld && !gWasFKeyPressed){ // long press
         if (!bKeyPressed) // released
             return; 
@@ -842,12 +873,6 @@ static void MAIN_Key_STAR(bool bKeyPressed, bool bKeyHeld)
         gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
         return;
     }
-
-    if (bKeyPressed) { // just pressed
-        return;
-    }
-    
-    // just released
     
     if (!gWasFKeyPressed) // pressed without the F-key
     {   
@@ -860,7 +885,6 @@ static void MAIN_Key_STAR(bool bKeyPressed, bool bKeyHeld)
 #endif      
         )
         {   // start entering a DTMF string
-            gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
             memcpy(gDTMF_InputBox, gDTMF_String, MIN(sizeof(gDTMF_InputBox), sizeof(gDTMF_String) - 1));
             gDTMF_InputBox_Index  = 0;
             gDTMF_InputMode       = true;
@@ -896,18 +920,13 @@ static void MAIN_Key_STAR(bool bKeyPressed, bool bKeyHeld)
 
 static void MAIN_Key_UP_DOWN(bool bKeyPressed, bool bKeyHeld, int8_t Direction)
 {
+    if (!gEeprom.SET_NAV) {
+        Direction = -Direction;
+    }
 
 #ifdef ENABLE_FEAT_F4HWN // Set Squelch F + UP or Down
     if(gWasFKeyPressed) {
-        switch(Direction)
-        {
-            case 1:
-                processFKeyFunction(KEY_UP, false);
-                break;
-            case -1:
-                processFKeyFunction(KEY_DOWN, false);
-                break;
-        }
+        processFKeyFunction(Direction == 1 ? KEY_UP : KEY_DOWN, true);
         return;
     }
 #endif
@@ -920,8 +939,10 @@ static void MAIN_Key_UP_DOWN(bool bKeyPressed, bool bKeyHeld, int8_t Direction)
     uint16_t Channel = gEeprom.ScreenChannel[gEeprom.TX_VFO];
 
     if (bKeyHeld || !bKeyPressed) { // key held or released
-        if (gInputBoxIndex > 0)
-            return; // leave if input box active
+        if (gInputBoxIndex > 0) {
+            gInputBoxIndex = 0;
+            gHasVfoBackup = false;
+        }
 
         if (!bKeyPressed) {
             if (!bKeyHeld || IS_FREQ_CHANNEL(Channel))
@@ -935,10 +956,6 @@ static void MAIN_Key_UP_DOWN(bool bKeyPressed, bool bKeyHeld, int8_t Direction)
         }
     }
     else { // short pressed
-        if (gInputBoxIndex > 0) {
-            gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
-            return;
-        }
         gBeepToPlay = BEEP_1KHZ_60MS_OPTIONAL;
     }
 
@@ -1039,16 +1056,8 @@ void MAIN_ProcessKeys(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
             MAIN_Key_MENU(bKeyPressed, bKeyHeld);
             break;
         case KEY_UP:
-            if(gEeprom.SET_NAV == 0)
-                MAIN_Key_UP_DOWN(bKeyPressed, bKeyHeld, -1);            
-            else
-                MAIN_Key_UP_DOWN(bKeyPressed, bKeyHeld, 1);
-            break;
         case KEY_DOWN:
-            if(gEeprom.SET_NAV == 0)
-                MAIN_Key_UP_DOWN(bKeyPressed, bKeyHeld, 1);
-            else
-                MAIN_Key_UP_DOWN(bKeyPressed, bKeyHeld, -1);
+            MAIN_Key_UP_DOWN(bKeyPressed, bKeyHeld, Key == KEY_UP ? 1 : -1);
             break;
         case KEY_EXIT:
             MAIN_Key_EXIT(bKeyPressed, bKeyHeld);
@@ -1067,4 +1076,4 @@ void MAIN_ProcessKeys(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
                 gBeepToPlay = BEEP_500HZ_60MS_DOUBLE_BEEP_OPTIONAL;
             break;
     }
-}
+}

App/app/menu.c

@@ -308,7 +308,7 @@ int MENU_GetLimits(uint8_t menu_id, int32_t *pMin, int32_t *pMax)
 
         case MENU_MIC:
             //*pMin = 0;
-            *pMax = 4;
+            *pMax = 8;
             break;
 
         case MENU_LIST_CH:
@@ -480,6 +480,7 @@ void MENU_AcceptSetting(void)
         case MENU_SQL:
             gEeprom.SQUELCH_LEVEL = gSubMenuSelection;
             gVfoConfigureMode     = VFO_CONFIGURE;
+            gRequestSaveSquelch   = true;
             break;
 
         case MENU_STEP:
@@ -1547,15 +1548,17 @@ static void MENU_Key_0_to_9(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
         return;
     }
 
-    if (UI_MENU_GetCurrentMenuId() == MENU_MEM_CH ||
-        UI_MENU_GetCurrentMenuId() == MENU_DEL_CH ||
-        UI_MENU_GetCurrentMenuId() == MENU_1_CALL ||
-        UI_MENU_GetCurrentMenuId() == MENU_S_PRI_CH_1 ||
-        UI_MENU_GetCurrentMenuId() == MENU_S_PRI_CH_2 ||
-        UI_MENU_GetCurrentMenuId() == MENU_MEM_NAME)
-    {   // enter 3-digit channel number
+    const int m = UI_MENU_GetCurrentMenuId();
 
-        if (gInputBoxIndex < 3)
+    if (m == MENU_MEM_CH ||
+        m == MENU_DEL_CH ||
+        m == MENU_1_CALL ||
+        m == MENU_S_PRI_CH_1 ||
+        m == MENU_S_PRI_CH_2 ||
+        m == MENU_MEM_NAME)
+    {   // enter 4-digit channel number
+
+        if (gInputBoxIndex < 4)
         {
             #ifdef ENABLE_VOICE
                 gAnotherVoiceID   = (VOICE_ID_t)Key;
@@ -1566,7 +1569,8 @@ static void MENU_Key_0_to_9(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
 
         gInputBoxIndex = 0;
 
-        Value = ((gInputBox[0] * 100) + (gInputBox[1] * 10) + gInputBox[2]) - 1;
+        //Value = ((gInputBox[0] * 100) + (gInputBox[1] * 10) + gInputBox[2]) - 1;
+        Value = ((gInputBox[0] * 1000) + (gInputBox[1] * 100) + (gInputBox[2] * 10) + gInputBox[3]) - 1;
 
         if (IS_MR_CHANNEL(Value))
         {
@@ -1691,19 +1695,21 @@ static void MENU_Key_MENU(const bool bKeyPressed, const bool bKeyHeld)
 
     if (!gIsInSubMenu)
     {
+        const int m = UI_MENU_GetCurrentMenuId();
+
         #ifdef ENABLE_VOICE
-            if (UI_MENU_GetCurrentMenuId() != MENU_SCR)
+            if (m != MENU_SCR)
                 gAnotherVoiceID = MenuList[gMenuCursor].voice_id;
         #endif
-        if (UI_MENU_GetCurrentMenuId() == MENU_UPCODE 
-            || UI_MENU_GetCurrentMenuId() == MENU_DWCODE 
+        if (m == MENU_UPCODE 
+            || m == MENU_DWCODE 
 #ifdef ENABLE_DTMF_CALLING 
-            || UI_MENU_GetCurrentMenuId() == MENU_ANI_ID
+            || m == MENU_ANI_ID
 #endif
             )
             return;
         #if 1
-            if (UI_MENU_GetCurrentMenuId() == MENU_DEL_CH || UI_MENU_GetCurrentMenuId() == MENU_MEM_NAME)
+            if (m == MENU_DEL_CH || m == MENU_MEM_NAME)
                 if (!RADIO_CheckValidChannel(gSubMenuSelection, false, 0))
                     return;  // invalid channel
         #endif
@@ -1711,7 +1717,7 @@ static void MENU_Key_MENU(const bool bKeyPressed, const bool bKeyHeld)
         gAskForConfirmation = 0;
         gIsInSubMenu        = true;
 
-//      if (UI_MENU_GetCurrentMenuId() != MENU_D_LIST)
+//      if (m != MENU_D_LIST)
         {
             gInputBoxIndex      = 0;
             edit_index          = -1;
@@ -1762,10 +1768,12 @@ static void MENU_Key_MENU(const bool bKeyPressed, const bool bKeyHeld)
 
     if (gIsInSubMenu)
     {
-        if (UI_MENU_GetCurrentMenuId() == MENU_RESET  ||
-            UI_MENU_GetCurrentMenuId() == MENU_MEM_CH ||
-            UI_MENU_GetCurrentMenuId() == MENU_DEL_CH ||
-            UI_MENU_GetCurrentMenuId() == MENU_MEM_NAME)
+        const int m = UI_MENU_GetCurrentMenuId();
+
+        if (m == MENU_RESET  ||
+            m == MENU_MEM_CH ||
+            m == MENU_DEL_CH ||
+            m == MENU_MEM_NAME)
         {
             switch (gAskForConfirmation)
             {
@@ -1778,7 +1786,7 @@ static void MENU_Key_MENU(const bool bKeyPressed, const bool bKeyHeld)
 
                     UI_DisplayMenu();
 
-                    if (UI_MENU_GetCurrentMenuId() == MENU_RESET)
+                    if (m == MENU_RESET)
                     {
                         #ifdef ENABLE_VOICE
                             AUDIO_SetVoiceID(0, VOICE_ID_CONFIRM);
@@ -1852,7 +1860,8 @@ static void MENU_Key_STAR(const bool bKeyPressed, const bool bKeyHeld)
         if (gRxVfo->Modulation ==  MODULATION_FM)
     #endif
     {
-        if ((UI_MENU_GetCurrentMenuId() == MENU_R_CTCS || UI_MENU_GetCurrentMenuId() == MENU_R_DCS) && gIsInSubMenu)
+        const int m = UI_MENU_GetCurrentMenuId();
+        if ((m == MENU_R_CTCS || m == MENU_R_DCS) && gIsInSubMenu)
         {   // scan CTCSS or DCS to find the tone/code of the incoming signal
             if (!SCANNER_IsScanning())
                 MENU_StartCssScan();
@@ -1873,6 +1882,10 @@ static void MENU_Key_UP_DOWN(bool bKeyPressed, bool bKeyHeld, int8_t Direction)
     uint16_t Channel;
     bool    bCheckScanList;
 
+    if (!gEeprom.SET_NAV && gIsInSubMenu) {
+        Direction = -Direction;
+    }
+
     if (UI_MENU_GetCurrentMenuId() == MENU_MEM_NAME && gIsInSubMenu && edit_index >= 0)
     {   // change the character
         if (bKeyPressed && edit_index < 10 && Direction != 0)
@@ -1920,9 +1933,11 @@ static void MENU_Key_UP_DOWN(bool bKeyPressed, bool bKeyHeld, int8_t Direction)
 
         gRequestDisplayScreen = DISPLAY_MENU;
 
-        if (UI_MENU_GetCurrentMenuId() != MENU_ABR
-            && UI_MENU_GetCurrentMenuId() != MENU_ABR_MIN
-            && UI_MENU_GetCurrentMenuId() != MENU_ABR_MAX
+        const int m = UI_MENU_GetCurrentMenuId();
+
+        if (m != MENU_ABR 
+            && m != MENU_ABR_MIN 
+            && m != MENU_ABR_MAX 
             && gEeprom.BACKLIGHT_TIME == 0) // backlight always off and not in the backlight menu
         {
             BACKLIGHT_TurnOff();
@@ -1948,8 +1963,10 @@ static void MENU_Key_UP_DOWN(bool bKeyPressed, bool bKeyHeld, int8_t Direction)
     }
 
     VFO = 0;
+    
+    const int m = UI_MENU_GetCurrentMenuId();
 
-    switch (UI_MENU_GetCurrentMenuId())
+    switch (m)
     {
         case MENU_DEL_CH:
         case MENU_1_CALL:
@@ -1965,19 +1982,21 @@ static void MENU_Key_UP_DOWN(bool bKeyPressed, bool bKeyHeld, int8_t Direction)
             return;
     }
 
-    if(UI_MENU_GetCurrentMenuId() == MENU_S_PRI_CH_1 || UI_MENU_GetCurrentMenuId() == MENU_S_PRI_CH_2)
+    if(m == MENU_S_PRI_CH_1 || m == MENU_S_PRI_CH_2)
     {
         static int16_t last;
 
-        if(Direction > 0 && gSubMenuSelection == MR_CHANNELS_MAX)
-        {
-            gSubMenuSelection = -1;
-            last = -1;
-        }
-        else if(Direction < 0 && gSubMenuSelection == MR_CHANNELS_MAX)
-        {
-            gSubMenuSelection = MR_CHANNELS_MAX;
-            last = MR_CHANNELS_MAX;
+        if(gSubMenuSelection == MR_CHANNELS_MAX) {
+            if(Direction > 0)
+            {
+                gSubMenuSelection = -1;
+                last = -1;
+            }
+            else if(Direction < 0)
+            {
+                gSubMenuSelection = MR_CHANNELS_MAX;
+                last = MR_CHANNELS_MAX;
+            }
         }
 
         Channel = RADIO_FindNextChannel(gSubMenuSelection + Direction, Direction, bCheckScanList, VFO);
@@ -2013,42 +2032,15 @@ void MENU_ProcessKeys(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
 {
     switch (Key)
     {
-        case KEY_0:
-        case KEY_1:
-        case KEY_2:
-        case KEY_3:
-        case KEY_4:
-        case KEY_5:
-        case KEY_6:
-        case KEY_7:
-        case KEY_8:
-        case KEY_9:
+        case KEY_0...KEY_9:
             MENU_Key_0_to_9(Key, bKeyPressed, bKeyHeld);
             break;
         case KEY_MENU:
             MENU_Key_MENU(bKeyPressed, bKeyHeld);
             break;
         case KEY_UP:
-            if(gEeprom.SET_NAV == 0) {
-                if(gIsInSubMenu)
-                    MENU_Key_UP_DOWN(bKeyPressed, bKeyHeld, -1);
-                else
-                    MENU_Key_UP_DOWN(bKeyPressed, bKeyHeld, 1);
-            }
-            else {
-                MENU_Key_UP_DOWN(bKeyPressed, bKeyHeld, 1);
-            }
-            break;
         case KEY_DOWN:
-            if(gEeprom.SET_NAV == 0) {
-                if(gIsInSubMenu)
-                    MENU_Key_UP_DOWN(bKeyPressed, bKeyHeld, 1);
-                else
-                    MENU_Key_UP_DOWN(bKeyPressed, bKeyHeld, -1);
-            }
-            else {
-                MENU_Key_UP_DOWN(bKeyPressed, bKeyHeld, -1);
-            }
+            MENU_Key_UP_DOWN(bKeyPressed, bKeyHeld, Key == KEY_UP ? 1 : -1);
             break;
         case KEY_EXIT:
             MENU_Key_EXIT(bKeyPressed, bKeyHeld);
@@ -2089,11 +2081,13 @@ void MENU_ProcessKeys(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
 
     if (gScreenToDisplay == DISPLAY_MENU)
     {
-        if (UI_MENU_GetCurrentMenuId() == MENU_VOL ||
+        const int m = UI_MENU_GetCurrentMenuId();
+
+        if (m == MENU_VOL ||
             #ifdef ENABLE_F_CAL_MENU
-                UI_MENU_GetCurrentMenuId() == MENU_F_CALI ||
+                m == MENU_F_CALI ||
             #endif
-            UI_MENU_GetCurrentMenuId() == MENU_BATCAL)
+            m == MENU_BATCAL)
         {
             gMenuCountdown = menu_timeout_long_500ms;
         }

App/app/scanner.c

@@ -32,7 +32,7 @@ DCS_CodeType_t    gScanCssResultType;
 uint8_t           gScanCssResultCode;
 bool              gScanSingleFrequency; // scan CTCSS/DCS codes for current frequency
 SCAN_SaveState_t  gScannerSaveState;
-uint8_t           gScanChannel;
+uint16_t          gScanChannel;
 uint32_t          gScanFrequency;
 SCAN_CssState_t   gScanCssState;
 uint8_t           gScanProgressIndicator;
@@ -52,7 +52,7 @@ static void SCANNER_Key_DIGITS(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
 
             gRequestDisplayScreen = DISPLAY_SCANNER;
 
-            if (gInputBoxIndex < 3) {
+            if (gInputBoxIndex < 4) {
 #ifdef ENABLE_VOICE
                 gAnotherVoiceID = (VOICE_ID_t)Key;
 #endif
@@ -61,13 +61,14 @@ static void SCANNER_Key_DIGITS(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
 
             gInputBoxIndex = 0;
 
-            uint16_t chan = ((gInputBox[0] * 100) + (gInputBox[1] * 10) + gInputBox[2]) - 1;
+            // uint16_t chan = ((gInputBox[0] * 100) + (gInputBox[1] * 10) + gInputBox[2]) - 1;
+            uint16_t chan = ((gInputBox[0] * 1000) + (gInputBox[1] * 100) + (gInputBox[2] * 10) + gInputBox[3]) - 1;
             if (IS_MR_CHANNEL(chan)) {
 #ifdef ENABLE_VOICE
                 gAnotherVoiceID = (VOICE_ID_t)Key;
 #endif
                 gShowChPrefix = RADIO_CheckValidChannel(chan, false, 0);
-                gScanChannel  = (uint8_t)chan;
+                gScanChannel  = chan;
                 return;
             }
         }
@@ -207,7 +208,7 @@ static void SCANNER_Key_MENU(bool bKeyPressed, bool bKeyHeld)
                 gTxVfo->freq_config_TX.Code     = gScanCssResultCode;
             }
 
-            uint8_t chan;
+            uint16_t chan;
             if (IS_MR_CHANNEL(gTxVfo->CHANNEL_SAVE)) {
                 chan = gScanChannel;
                 gEeprom.MrChannel[gEeprom.TX_VFO] = chan;
@@ -256,6 +257,10 @@ static void SCANNER_Key_UP_DOWN(bool bKeyPressed, bool pKeyHeld, int8_t Directio
         gBeepToPlay    = BEEP_1KHZ_60MS_OPTIONAL;
     }
 
+    if (!gEeprom.SET_NAV) {
+        Direction = -Direction;
+    }
+
     if (gScannerSaveState == SCAN_SAVE_CHAN_SEL) {
         gScanChannel          = NUMBER_AddWithWraparound(gScanChannel, Direction, 0, MR_CHANNEL_LAST);
         gShowChPrefix         = RADIO_CheckValidChannel(gScanChannel, false, 0);
@@ -275,10 +280,8 @@ void SCANNER_ProcessKeys(KEY_Code_t Key, bool bKeyPressed, bool bKeyHeld)
             SCANNER_Key_MENU(bKeyPressed, bKeyHeld);
             break;
         case KEY_UP:
-            SCANNER_Key_UP_DOWN(bKeyPressed, bKeyHeld,  1);
-            break;
         case KEY_DOWN:
-            SCANNER_Key_UP_DOWN(bKeyPressed, bKeyHeld, -1);
+            SCANNER_Key_UP_DOWN(bKeyPressed, bKeyHeld, Key == KEY_UP ? 1 : -1);
             break;
         case KEY_EXIT:
             SCANNER_Key_EXIT(bKeyPressed, bKeyHeld);

App/app/scanner.h

@@ -40,7 +40,7 @@ extern DCS_CodeType_t    gScanCssResultType;
 extern uint8_t           gScanCssResultCode;
 extern bool              gScanSingleFrequency;
 extern SCAN_SaveState_t  gScannerSaveState;
-extern uint8_t           gScanChannel;
+extern uint16_t          gScanChannel;
 extern uint32_t          gScanFrequency;
 extern SCAN_CssState_t   gScanCssState;
 extern uint8_t           gScanProgressIndicator;

App/app/spectrum.c

@@ -270,16 +270,6 @@ static void GUI_DisplaySmallest(const char *pString, uint8_t x, uint8_t y,
 
 // Utility functions
 
-static KEY_Code_t GetKey()
-{
-    KEY_Code_t btn = KEYBOARD_Poll();
-    if (btn == KEY_INVALID && GPIO_IsPttPressed())
-    {
-        btn = KEY_PTT;
-    }
-    return btn;
-}
-
 static int clamp(int v, int min, int max)
 {
     return v <= min ? min : (v >= max ? max : v);
@@ -787,11 +777,13 @@ static void ToggleBacklight()
     settings.backlightState = !settings.backlightState;
     if (settings.backlightState)
     {
-        BACKLIGHT_TurnOn();
+        // BACKLIGHT_TurnOn();
+        BACKLIGHT_SetBrightness(gEeprom.BACKLIGHT_MAX);
     }
     else
     {
-        BACKLIGHT_TurnOff();
+        // BACKLIGHT_TurnOff();
+        BACKLIGHT_SetBrightness(gEeprom.BACKLIGHT_MIN);
     }
 }
 
@@ -1185,37 +1177,32 @@ static void DrawArrow(uint8_t x)
 
 static void OnKeyDown(uint8_t key)
 {
-    bool nav = (gEeprom.SET_NAV != 0);
+    bool nav = gEeprom.SET_NAV;
+    bool isTrue = false;
 
     switch (key)
     {
     case KEY_3:
-        UpdateDBMax(true);
-        break;
+        isTrue = true;
+        [[fallthrough]];
     case KEY_9:
-        UpdateDBMax(false);
+        UpdateDBMax(isTrue);
         break;
     case KEY_1:
-        UpdateScanStep(true);
-        break;
+        isTrue = true;
+        [[fallthrough]];
     case KEY_7:
-        UpdateScanStep(false);
+        UpdateScanStep(isTrue);
         break;
     case KEY_2:
-        UpdateFreqChangeStep(true);
-        break;
+        isTrue = true;
+        [[fallthrough]];
     case KEY_8:
-        UpdateFreqChangeStep(false);
+        UpdateFreqChangeStep(isTrue);
         break;
     case KEY_UP:
-#ifdef ENABLE_SCAN_RANGES
-        if (!gScanRangeStart) {
-#endif
-        UpdateCurrentFreq(nav);
-#ifdef ENABLE_SCAN_RANGES
-        }
-#endif
-        break;
+        nav = !nav;
+        [[fallthrough]];
     case KEY_DOWN:
 #ifdef ENABLE_SCAN_RANGES
         if (!gScanRangeStart) {
@@ -1229,10 +1216,10 @@ static void OnKeyDown(uint8_t key)
         Blacklist();
         break;
     case KEY_STAR:
-        UpdateRssiTriggerLevel(true);
-        break;
+        isTrue = true;
+        [[fallthrough]];
     case KEY_F:
-        UpdateRssiTriggerLevel(false);
+        UpdateRssiTriggerLevel(isTrue);
         break;
     case KEY_5:
 #ifdef ENABLE_SCAN_RANGES
@@ -1285,21 +1272,10 @@ static void OnKeyDownFreqInput(uint8_t key)
 {
     switch (key)
     {
-    case KEY_0:
-    case KEY_1:
-    case KEY_2:
-    case KEY_3:
-    case KEY_4:
-    case KEY_5:
-    case KEY_6:
-    case KEY_7:
-    case KEY_8:
-    case KEY_9:
+    case KEY_0...KEY_9:
     case KEY_STAR:
-        UpdateFreqInput(key);
-        break;
     case KEY_EXIT:
-        if (freqInputIndex == 0)
+        if (freqInputIndex == 0 && key == KEY_EXIT)
         {
             SetState(previousState);
             break;
@@ -1330,23 +1306,20 @@ static void OnKeyDownFreqInput(uint8_t key)
 
 void OnKeyDownStill(KEY_Code_t key)
 {
-    bool nav = (gEeprom.SET_NAV != 0);
+    bool nav = gEeprom.SET_NAV;
+    bool isTrue = false;
 
     switch (key)
     {
     case KEY_3:
-        UpdateDBMax(true);
-        break;
+        isTrue = true;
+        [[fallthrough]];
     case KEY_9:
-        UpdateDBMax(false);
+        UpdateDBMax(isTrue);
         break;
     case KEY_UP:
-        if (menuState) {
-            SetRegMenuValue(menuState, nav);
-            break;
-        }
-        UpdateCurrentFreqStill(nav);
-        break;
+        nav = !nav;
+        [[fallthrough]];
     case KEY_DOWN:
         if (menuState) {
             SetRegMenuValue(menuState, !nav);
@@ -1355,10 +1328,10 @@ void OnKeyDownStill(KEY_Code_t key)
         UpdateCurrentFreqStill(!nav);
         break;
     case KEY_STAR:
-        UpdateRssiTriggerLevel(true);
-        break;
+        isTrue = true;
+        [[fallthrough]];
     case KEY_F:
-        UpdateRssiTriggerLevel(false);
+        UpdateRssiTriggerLevel(isTrue);
         break;
     case KEY_5:
         FreqInput();
@@ -1381,14 +1354,7 @@ void OnKeyDownStill(KEY_Code_t key)
         BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1_RED, true); */
         break;
     case KEY_MENU:
-        if (menuState == ARRAY_SIZE(registerSpecs) - 1)
-        {
-            menuState = 1;
-        }
-        else
-        {
-            menuState++;
-        }
+        menuState = (menuState == ARRAY_SIZE(registerSpecs) - 1) ? 1 : menuState + 1;
         redrawScreen = true;
         break;
     case KEY_EXIT:
@@ -1541,7 +1507,7 @@ static void Render()
 static bool HandleUserInput()
 {
     kbd.prev = kbd.current;
-    kbd.current = GetKey();
+    kbd.current = KEYBOARD_GetKey();
 
     if (kbd.current != KEY_INVALID && kbd.current == kbd.prev)
     {
@@ -1691,16 +1657,23 @@ static void UpdateListening()
 
 static void Tick()
 {
-#ifdef ENABLE_AM_FIX
+#ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
+    // Parse incoming packets on every tick so serial keys are never missed,
+    // regardless of whether the screen needs redrawing.
+    SCREENSHOT_ParseInput();
+#endif
+
     if (gNextTimeslice)
     {
         gNextTimeslice = false;
+#ifdef ENABLE_AM_FIX
         if (settings.modulationType == MODULATION_AM && !lockAGC)
         {
             AM_fix_10ms(vfo); // allow AM_Fix to apply its AGC action
         }
-    }
 #endif
+        BACKLIGHT_Update();
+    }
 
 #ifdef ENABLE_SCAN_RANGES
     if (gNextTimeslice_500ms)
@@ -1760,7 +1733,7 @@ static void Tick()
         Render();
         // For screenshot
         #ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
-            getScreenShot(false);
+            SCREENSHOT_Update(false);
         #endif
         redrawScreen = false;
     }
@@ -1768,6 +1741,8 @@ static void Tick()
 
 void APP_RunSpectrum()
 {
+    settings.backlightState = gEeprom.BACKLIGHT_TIME == 0 ? false : true;
+
     // TX here coz it always? set to active VFO
     vfo = gEeprom.TX_VFO;
 #ifdef ENABLE_FEAT_F4HWN_SPECTRUM
@@ -1830,4 +1805,6 @@ void APP_RunSpectrum()
     {
         Tick();
     }
+
+    BACKLIGHT_TurnOn();
 }

App/audio.c

@@ -53,12 +53,7 @@ void AUDIO_PlayBeep(BEEP_Type_t Beep)
 #endif
        !gEeprom.BEEP_CONTROL)
         return;
-
-#ifdef ENABLE_AIRCOPY
-    if (gScreenToDisplay == DISPLAY_AIRCOPY)
-        return;
-#endif
-
+        
     if (gCurrentFunction == FUNCTION_RECEIVE)
         return;
 
@@ -182,11 +177,19 @@ void AUDIO_PlayBeep(BEEP_Type_t Beep)
     SYSTEM_DelayMs(5);
     BK4819_WriteRegister(BK4819_REG_71, ToneConfig);
 
+#ifdef ENABLE_FMRADIO
+    const bool isFmRadio = gFmRadioMode;
+    
+    if (isFmRadio)
+        SYSTEM_DelayMs(10);
+#endif
+
+
     if (gEnableSpeaker)
         AUDIO_AudioPathOn();
 
 #ifdef ENABLE_FMRADIO
-    if (gFmRadioMode)
+    if (isFmRadio)
         BK1080_Mute(false);
 #endif
 

App/bitmaps.c

@@ -157,15 +157,6 @@ const uint8_t BITMAP_USB_C[9] =
     };
 #endif
 
-const uint8_t BITMAP_Antenna[5] =
-{
-    0b00000011,
-    0b00000101,
-    0b01111111,
-    0b00000101,
-    0b00000011
-};
-
 const uint8_t BITMAP_VFO_Lock[7] =
 {
     0b00111100,
@@ -177,6 +168,7 @@ const uint8_t BITMAP_VFO_Lock[7] =
     0b00111100,
 };
 
+/*
 const uint8_t BITMAP_VFO_Default[7] =
 {
     0b01111111,
@@ -198,6 +190,42 @@ const uint8_t BITMAP_VFO_NotDefault[7] =
     0b00010100,
     0b00001000
 };
+*/
+
+// Compact arrow
+const uint8_t BITMAP_VFO_Default[7] =
+{
+    0b00111110,
+    0b00111110,
+    0b00011100,
+    0b00011100,
+    0b00001000,
+    0b00001000,
+    0b00000000
+};
+
+// Compact empty arrow
+const uint8_t BITMAP_VFO_NotDefault[7] =
+{
+    0b00100010,
+    0b00100010,
+    0b00010100,
+    0b00010100,
+    0b00001000,
+    0b00001000,
+    0b00000000
+};
+
+const uint8_t BITMAP_VFO_Empty[7] =
+{
+    0b00000000,
+    0b00000000,
+    0b00000000,
+    0b00000000,
+    0b00000000,
+    0b00000000,
+    0b00000000
+};
 
 const uint8_t BITMAP_compand[6] =
 {

App/bitmaps.h

@@ -35,9 +35,9 @@ extern const uint8_t BITMAP_NotReady[7];
     extern const uint8_t gFontVox[2][6];
 #endif
 
-extern const uint8_t BITMAP_Antenna[5];
 extern const uint8_t BITMAP_VFO_Default[7];
 extern const uint8_t BITMAP_VFO_NotDefault[7];
+extern const uint8_t BITMAP_VFO_Empty[7];
 extern const uint8_t BITMAP_VFO_Lock[7];
 extern const uint8_t BITMAP_PowerUser[3];
 extern const uint8_t BITMAP_compand[6];

App/driver/backlight.c

@@ -31,7 +31,7 @@
     #include "misc.h"
 #endif
 
-#define PWM_FREQ 320
+#define PWM_FREQ 4000
 #define DUTY_CYCLE_LEVELS 64
 
 #define DUTY_CYCLE_ON_VALUE GPIO_PIN_MASK(GPIO_PIN_BACKLIGHT)
@@ -44,8 +44,14 @@ static uint32_t dutyCycle[DUTY_CYCLE_LEVELS];
 
 // this is decremented once every 500ms
 uint16_t gBacklightCountdown_500ms = 0;
+bool gUpdateBacklight = false;
 bool backlightOn;
 
+static uint8_t currentIndex = 0;
+static int16_t currentBrightness = 0;
+static int16_t targetBrightness = 0;
+static int16_t fadeStep = 0;
+
 #ifdef ENABLE_FEAT_F4HWN
     const uint8_t value[] = {
         0,    // 0 off
@@ -110,6 +116,12 @@ static void BACKLIGHT_Sound(void)
     gK5startup = false;
 }
 
+void BACKLIGHT_UpdateTickless(void) {
+    while(gUpdateBacklight) {
+        BACKLIGHT_Update();
+        SYSTEM_DelayMs(10);
+    }
+}
 
 void BACKLIGHT_TurnOn(void)
 {
@@ -134,27 +146,23 @@ void BACKLIGHT_TurnOn(void)
 
     backlightOn = true;
 
-#ifdef ENABLE_FEAT_F4HWN
-    if(gK5startup == true) {
-        #if defined(ENABLE_FMRADIO) && defined(ENABLE_SPECTRUM)
-            BACKLIGHT_SetBrightness(gEeprom.BACKLIGHT_MAX);
-        #else
-            for(uint8_t i = 0; i <= gEeprom.BACKLIGHT_MAX; i++)
-            {
-                BACKLIGHT_SetBrightness(i);
-                SYSTEM_DelayMs(50);
-            }
-        #endif
-
-        BACKLIGHT_Sound();
-    }
-    else
-    {
-        BACKLIGHT_SetBrightness(gEeprom.BACKLIGHT_MAX);
-    }
-#else
     BACKLIGHT_SetBrightness(gEeprom.BACKLIGHT_MAX);
+
+#ifdef ENABLE_FEAT_F4HWN
+    if(gK5startup == true)
+#else
+    static bool startup = true;
+    
+    if(startup)
 #endif
+    {
+        BACKLIGHT_UpdateTickless();
+#ifdef ENABLE_FEAT_F4HWN
+        BACKLIGHT_Sound();
+#else
+        startup = false;
+#endif
+    }
 
     switch (gEeprom.BACKLIGHT_TIME) {
         default:
@@ -190,18 +198,11 @@ bool BACKLIGHT_IsOn()
     return backlightOn;
 }
 
-static uint8_t currentBrightness = 0;
-
-void BACKLIGHT_SetBrightness(uint8_t brigtness)
+static void BACKLIGHT_SetHardwareBrightness(uint8_t brightness)
 {
     // printf("BL: %d\n", brigtness);
 
-    if (currentBrightness == brigtness)
-    {
-        return;
-    }
-
-    if (0 == brigtness)
+    if (0 == brightness)
     {
         LL_TIM_DisableCounter(TIMx);
         LL_DMA_DisableChannel(DMA1, DMA_CHANNEL);
@@ -210,7 +211,7 @@ void BACKLIGHT_SetBrightness(uint8_t brigtness)
     }
     else
     {
-        const uint32_t level = (uint32_t)(value[brigtness]) * DUTY_CYCLE_LEVELS / 255;
+        const uint32_t level = (uint32_t)(brightness) * DUTY_CYCLE_LEVELS / 255;
         if (level >= DUTY_CYCLE_LEVELS)
         {
             LL_TIM_DisableCounter(TIMx);
@@ -231,11 +232,45 @@ void BACKLIGHT_SetBrightness(uint8_t brigtness)
             }
         }
     }
+}
 
-    currentBrightness = brigtness;
+void BACKLIGHT_Update(void)
+{
+    if (gUpdateBacklight) {
+        currentBrightness += fadeStep;
+
+        if ((fadeStep > 0 && currentBrightness >= targetBrightness) || 
+            (fadeStep < 0 && currentBrightness <= targetBrightness)) {
+            currentBrightness = targetBrightness;
+            gUpdateBacklight = false;
+        }
+
+        BACKLIGHT_SetHardwareBrightness((uint8_t)currentBrightness);
+    }
+}
+
+void BACKLIGHT_SetBrightness(uint8_t targetIndex)
+{
+    if (currentIndex == targetIndex) {
+        return;
+    }
+
+    currentIndex = targetIndex;
+    targetBrightness = value[targetIndex];
+
+    int16_t diff = targetBrightness - currentBrightness;
+
+    if (diff == 0) {
+        gUpdateBacklight = false;
+        return;
+    }
+    
+    fadeStep = diff > 0 ? -(-diff >> 4) : diff >> 4;
+
+    gUpdateBacklight = true;
 }
 
 uint8_t BACKLIGHT_GetBrightness(void)
 {
-    return currentBrightness;
+    return currentIndex;
 }

App/driver/backlight.h

@@ -40,10 +40,12 @@ typedef enum {
 #endif
 
 void BACKLIGHT_InitHardware();
+void BACKLIGHT_UpdateTickless(void);
 void BACKLIGHT_TurnOn();
 void BACKLIGHT_TurnOff();
 bool BACKLIGHT_IsOn();
 void BACKLIGHT_SetBrightness(uint8_t brigtness);
+void BACKLIGHT_Update(void);
 uint8_t BACKLIGHT_GetBrightness(void);
 
 #endif

App/driver/bk4819.h

@@ -116,6 +116,10 @@ void     BK4819_TurnsOffTones_TurnsOnRX(void);
 #endif
 void     BK4819_ResetFSK(void);
 void     BK4819_Idle(void);
+#ifdef ENABLE_BYP_RAW_DEMODULATORS
+void     BK4819_EnterBypass(void);
+void     BK4819_EnterRaw(void);
+#endif
 void     BK4819_ExitBypass(void);
 void     BK4819_PrepareTransmit(void);
 void     BK4819_TxOn_Beep(void);

App/driver/bk4829.c

@@ -334,45 +334,9 @@ void BK4819_SetAGC(bool enable)
 
 void BK4819_InitAGC(bool amModulation)
 {
-    // REG_10, REG_11, REG_12 REG_13, REG_14
-    //
-    // Rx AGC Gain Table[]. (Index Max->Min is 3,2,1,0,-1)
-    //
-    // <15:10> ???
-    //
-    // <9:8>   LNA Gain Short
-    //         3 =   0dB  <<<       1o11                read from spectrum          reference manual
-    //         2 =                  -24dB               -19                          -11
-    //         1 =                  -30dB               -24                          -16
-    //         0 =                  -33dB               -28                          -19
-    //
-    // <7:5>   LNA Gain
-    //         7 =   0dB
-    //         6 =  -2dB
-    //         5 =  -4dB
-    //         4 =  -6dB
-    //         3 =  -9dB
-    //         2 = -14dB <<<
-    //         1 = -19dB
-    //         0 = -24dB
-    //
-    // <4:3>   MIXER Gain
-    //         3 =   0dB <<<
-    //         2 =  -3dB
-    //         1 =  -6dB
-    //         0 =  -8dB
-    //
-    // <2:0>   PGA Gain
-    //         7 =   0dB
-    //         6 =  -3dB <<<
-    //         5 =  -6dB
-    //         4 =  -9dB
-    //         3 = -15dB
-    //         2 = -21dB
-    //         1 = -27dB
-    //         0 = -33dB
-    //
 
+    /*
+    // Old strategy
     BK4819_WriteRegister(BK4819_REG_13, 0x03BE);  // 0x03BE / 000000 11 101 11 110 /  -7dB
     BK4819_WriteRegister(BK4819_REG_12, 0x037B);  // 0x037B / 000000 11 011 11 011 / -24dB
     BK4819_WriteRegister(BK4819_REG_11, 0x027B);  // 0x027B / 000000 10 011 11 011 / -43dB
@@ -387,7 +351,21 @@ void BK4819_InitAGC(bool amModulation)
     }
 
     BK4819_WriteRegister(BK4819_REG_7B, 0x8420);
+    */
 
+    // New strategy
+    // Keep the runtime AGC profile aligned with the stock BK4829 firmware
+    // until modulation-specific AGC changes are proven on hardware.
+
+    (void)amModulation;
+
+    BK4819_WriteRegister(BK4819_REG_10, 0x0318);
+    BK4819_WriteRegister(BK4819_REG_11, 0x033A);
+    BK4819_WriteRegister(BK4819_REG_12, 0x03DB);
+    BK4819_WriteRegister(BK4819_REG_13, 0x03DF);
+    BK4819_WriteRegister(BK4819_REG_14, 0x0210);
+    BK4819_WriteRegister(BK4819_REG_49, 0x2AB2);
+    BK4819_WriteRegister(BK4819_REG_7B, 0x73DC);
 }
 
 int8_t BK4819_GetRxGain_dB(void)
@@ -625,100 +603,91 @@ void BK4819_EnableVox(uint16_t VoxEnableThreshold, uint16_t VoxDisableThreshold)
 
 void BK4819_SetFilterBandwidth(const BK4819_FilterBandwidth_t Bandwidth, const bool weak_no_different)
 {
-    // REG_43
-    // <15>    0 ???
+    (void)weak_no_different;
+
+    // REG_43 on BK4829, per BK4829 Registers Table.
     //
-    // <14:12> 4 RF filter bandwidth
-    //         0 = 1.7  kHz
-    //         1 = 2.0  kHz
-    //         2 = 2.5  kHz
-    //         3 = 3.0  kHz
-    //         4 = 3.75 kHz
-    //         5 = 4.0  kHz
-    //         6 = 4.25 kHz
-    //         7 = 4.5  kHz
-    // if <5> == 1, RF filter bandwidth * 2
+    // <14:12> RF filter bandwidth (Apass = 0.1dB)
+    //         000 = 2.0 kHz
+    //         001 = 2.5 kHz
+    //         010 = 3.0 kHz
+    //         011 = 3.5 kHz
+    //         100 = 4.0 kHz
+    //         101 = 4.5 kHz
+    //         110 = 5.0 kHz
+    //         111 = 5.5 kHz
+    // if REG_43<5> == 1, RF filter bandwidth *= 2
     //
-    // <11:9>  0 RF filter bandwidth when signal is weak
-    //         0 = 1.7  kHz
-    //         1 = 2.0  kHz
-    //         2 = 2.5  kHz
-    //         3 = 3.0  kHz
-    //         4 = 3.75 kHz
-    //         5 = 4.0  kHz
-    //         6 = 4.25 kHz
-    //         7 = 4.5  kHz
-    // if <5> == 1, RF filter bandwidth * 2
+    // <11:9> RF filter bandwidth when signal is weak (Apass = 0.1dB)
+    //         000 = 2.0 kHz
+    //         001 = 2.5 kHz
+    //         010 = 3.0 kHz
+    //         011 = 3.5 kHz
+    //         100 = 4.0 kHz
+    //         101 = 4.5 kHz
+    //         110 = 5.0 kHz
+    //         111 = 5.5 kHz
+    // if REG_43<5> == 1, RF filter bandwidth *= 2
     //
-    // <8:6>   1 AFTxLPF2 filter Band Width
-    //         1 = 2.5  kHz (for 12.5k channel space)
-    //         2 = 2.75 kHz
-    //         0 = 3.0  kHz (for 25k   channel space)
-    //         3 = 3.5  kHz
-    //         4 = 4.5  kHz
-    //         5 = 4.25 kHz
-    //         6 = 4.0  kHz
-    //         7 = 3.75 kHz
+    // <8:6> AF Tx LPF2 filter bandwidth (Apass = 1dB)
+    //         100 = 5.5 kHz
+    //         101 = 5.0 kHz
+    //         110 = 4.5 kHz
+    //         111 = 4.0 kHz
+    //         000 = 3.0 kHz
+    //         001 = 2.5 kHz
+    //         010 = 2.75 kHz
+    //         011 = 3.5 kHz
     //
-    // <5:4>   0 BW Mode Selection
-    //         0 = 12.5k
-    //         1 =  6.25k
-    //         2 = 25k/20k
+    // <5:4> BW mode selection
+    //         00 = 12.5k
+    //         01 =  6.25k
+    //         10 = 25k/20k
     //
-    // <3>     1 ???
+    // <2> gain after FM demodulation
+    //         0 = 0 dB
+    //         1 = 6 dB
     //
-    // <2>     0 Gain after FM Demodulation
-    //         0 = 0dB
-    //         1 = 6dB
-    //
-    // <1:0>   0 ???
+    // <3> and <1:0> remain undocumented here.
 
     uint16_t val = 0;
     switch (Bandwidth)
     {
         case BK4819_FILTER_BW_WIDE: // 25kHz
-            // if (weak_no_different) {
-            //     // make the RX bandwidth the same with weak signals
-            //     val = 0x3628; // Old value 0x49a8 < v3.6
-            // } else {
-            //     // with weak RX signals the RX bandwidth is reduced
-            //     val = 0x3428; // Old value 0x45a8 < v3.6
-            // }
+            // 0x3028 = (0b011 << 12) | (0b000 << 9) | (0b000 << 6) |
+            //          (0b10 << 4)  | (1 << 3)
+            //        = RF 3.5 kHz and weak-RF 2.0 kHz, both doubled because
+            //          bit<5> is set in 25k/20k mode => RF 7.0 kHz, weak-RF
+            //          4.0 kHz, AF Tx LPF2 3.0 kHz, FM gain 0 dB.
             val = 0x3028;
             break;
 
         case BK4819_FILTER_BW_NARROW:   // 12.5kHz
-            // if (weak_no_different) {
-            //     // make the RX bandwidth the same with weak signals
-            //     val = 0x3648; // Old value 0x4808 < v3.6
-            // } else {
-            //     // with weak RX signals the RX bandwidth is reduced
-            //     val = 0x3448; // Old value 0x4408 < v3.6
-            // }
+            // 0x4048 = (0b100 << 12) | (0b000 << 9) | (0b001 << 6) |
+            //          (0b00 << 4)  | (1 << 3)
+            //        = RF 4.0 kHz, weak-RF 2.0 kHz, AF Tx LPF2 2.5 kHz,
+            //          12.5k mode, FM gain 0 dB.
             val = 0x4048;
             break;
 
         case BK4819_FILTER_BW_NARROWER: // 6.25kHz
-            // if (weak_no_different) {
-            //     // make the RX bandwidth the same with weak signals
-            //     val = 0x1348; // Old value 0x3658 < v3.6
-            // } else {
-            //     // with weak RX signals the RX bandwidth is reduced
-            //     val = 0x1148; // Old value 0x3658 < v3.6
-            // }
+            // 0x205C = (0b010 << 12) | (0b000 << 9) | (0b001 << 6) |
+            //          (0b01 << 4)  | (1 << 3)     | (1 << 2)
+            //        = RF 3.0 kHz, weak-RF 2.0 kHz, AF Tx LPF2 2.5 kHz,
+            //          6.25k mode, FM gain +6 dB.
             val = 0x205C;
             break;
 
-        case BK4819_FILTER_BW_AM:   // 8.33kHz
-            // if (weak_no_different) {
-            //     // make the RX bandwidth the same with weak signals
-            //     val = 0x4858;
-            // } else {
-            //     // with weak RX signals the RX bandwidth is reduced
-            //     val = 0x4458;
-            // }
+        case BK4819_FILTER_BW_AM:   // Stock AM preset
+            // 0x345C = (0b011 << 12) | (0b010 << 9) | (0b001 << 6) |
+            //          (0b01 << 4)  | (1 << 3)     | (1 << 2)
+            //        = RF 3.5 kHz, weak-RF 3.0 kHz, AF Tx LPF2 2.5 kHz,
+            //          6.25k mode, bit<2> set. The "8.33kHz AM" label used in
+            //          the codebase is functional/empirical; it does not come
+            //          directly from the BW mode bits of REG_43.
             val = 0x345C;
             break;
+
         default:
             val = 0x5C;
             break;
@@ -797,21 +766,20 @@ void BK4819_SetupSquelch(
     // <13:11> 5 Squelch = open  Delay Setting
     //         0 ~ 7
     //
-    // <10:9>  7 Squelch = close Delay Setting
+    // <10:9>  3 Squelch = close Delay Setting
     //         0 ~ 3
     //
-    // <8>     0 ???
+    // <8>     1 ???
     //
     // <7:0>   8 Glitch threshold for Squelch = open
     //         0 ~ 255
     //
-    BK4819_WriteRegister(BK4819_REG_4E,  // 01 101 11 1 00000000
-
-        // original (*)
-    (1u << 14) |                  //  1 ???
-    (5u << 11) |                  // *5  squelch = open  delay .. 0 ~ 7
-    (6u <<  9) |                  // *3  squelch = close delay .. 0 ~ 3
-    SquelchOpenGlitchThresh);     //  0 ~ 255
+    BK4819_WriteRegister(BK4819_REG_4E,
+    (1u << 14) |                  // 1 ???
+    (5u << 11) |                  // 5 squelch = open  delay .. 0 ~ 7
+    (3u <<  9) |                  // 3 squelch = close delay .. 0 ~ 3
+    (1u <<  8) |                  // 1 ??? (matches stock BK4829)
+    SquelchOpenGlitchThresh);     // 0 ~ 255
 
 
     // REG_4F
@@ -1154,45 +1122,62 @@ void BK4819_Idle(void)
     BK4819_WriteRegister(BK4819_REG_30, 0x0000);
 }
 
+#ifdef ENABLE_BYP_RAW_DEMODULATORS
+void BK4819_EnterBypass(void)
+{
+    // Keep AF output on normal path (REG_47 mode 0x1 is documented on BK4829).
+    BK4819_SetAF(BK4819_AF_FM);
+
+    // Bypass all AF filters (Rx + Tx) as recommended for digital bypass mode.
+    // REG_2B:
+    //  bit10: Disable AF Rx HPF300
+    //  bit 9: Disable AF Rx LPF3K
+    //  bit 8: Disable AF Rx de-emphasis
+    //  bit 2: Disable AF Tx HPF300
+    //  bit 1: Disable AF Tx LPF1
+    //  bit 0: Disable AF Tx pre-emphasis
+    uint16_t reg2b = BK4819_ReadRegister(BK4819_REG_2B);
+    reg2b |= (1u << 10) | (1u << 9) | (1u << 8) | (1u << 2) | (1u << 1) | (1u << 0);
+    BK4819_WriteRegister(BK4819_REG_2B, reg2b);
+
+    // Keep AGC/AFC behavior aligned with FM-like bypass experiments.
+    BK4819_SetRegValue(afcDisableRegSpec, false);
+}
+
+void BK4819_EnterRaw(void)
+{
+    // Keep AF output on a documented mode.
+    BK4819_SetAF(BK4819_AF_FM);
+
+    // RAW profile: bypass RX AF filters only, keep TX filter path unchanged.
+    // REG_2B:
+    //  bit10: Disable AF Rx HPF300
+    //  bit 9: Disable AF Rx LPF3K
+    //  bit 8: Disable AF Rx de-emphasis
+    uint16_t reg2b = BK4819_ReadRegister(BK4819_REG_2B);
+    reg2b |= (1u << 10) | (1u << 9) | (1u << 8);
+    reg2b &= ~((1u << 2) | (1u << 1) | (1u << 0));
+    BK4819_WriteRegister(BK4819_REG_2B, reg2b);
+
+    // RAW profile keeps AFC disabled to preserve discriminator-like behavior.
+    BK4819_SetRegValue(afcDisableRegSpec, true);
+}
+#endif
+
 void BK4819_ExitBypass(void)
 {
     BK4819_SetAF(BK4819_AF_MUTE);
 
-    // REG_7E
-    //
-    // <15>    0 AGC fix mode
-    //         1 = fix
-    //         0 = auto
-    //
-    // <14:12> 3 AGC fix index
-    //         3 ( 3) = max
-    //         2 ( 2)
-    //         1 ( 1)
-    //         0 ( 0)
-    //         7 (-1)
-    //         6 (-2)
-    //         5 (-3)
-    //         4 (-4) = min
-    //
-    // <11:6>  0 ???
-    //
-    // <5:3>   5 DC filter band width for Tx (MIC In)
-    //         0 ~ 7
-    //         0 = bypass DC filter
-    //
-    // <2:0>   6 DC filter band width for Rx (I.F In)
-    //         0 ~ 7
-    //         0 = bypass DC filter
-    //
+#ifdef ENABLE_BYP_RAW_DEMODULATORS
+    // Restore normal AF filters.
+    uint16_t reg2b = BK4819_ReadRegister(BK4819_REG_2B);
+    reg2b &= ~((1u << 10) | (1u << 9) | (1u << 8) | (1u << 2) | (1u << 1) | (1u << 0));
+    BK4819_WriteRegister(BK4819_REG_2B, reg2b);
+#endif
 
+    // Keep existing REG_7E logic from your current implementation.
     uint16_t regVal = BK4819_ReadRegister(BK4819_REG_7E);
-
-    // 0x302E / 0 011 000000 101 110
-    BK4819_WriteRegister(BK4819_REG_7E, (regVal & ~(0b111 << 3))
-
-        | (5u <<  3)       // 5  DC Filter band width for Tx (MIC In)
-
-    );
+    BK4819_WriteRegister(BK4819_REG_7E, (regVal & ~(0b111 << 3)) | (5u << 3));
 }
 
 void BK4819_PrepareTransmit(void)

App/driver/eeprom_compat.c

@@ -48,7 +48,8 @@ static const AddrMapping_t ADDR_MAPPINGS[] = {
     _MK_MAPPING(0x006000, 0x006000, 0x007000),  // 256 MR Name * 16 Bytes
     _MK_MAPPING(0x007000, 0x007000, 0x008000),  // 256 MR Name * 16 Bytes
 
-    _MK_MAPPING(0x008000, 0x008000, 0x00880E),  // 1024 MR  + 7 VFO Attributes * 2 Bytes (ex 0x002000)
+    _MK_MAPPING(0x008000, 0x008000, 0x00886E),  // 1024 MR  + 7 VFO Attributes * 2 Bytes (ex 0x002000) 0x008000 -> 0x00880E
+                                                // List name * 4 Bytes 0x00880E -> 0x00886E
 
     _MK_MAPPING(0x009000, 0x009000, 0x0090D6),  // 14 VFO * 16 Bytes (ex 0x001000)
 

App/driver/keyboard.c

@@ -27,6 +27,84 @@ KEY_Code_t gKeyReading1     = KEY_INVALID;
 uint16_t   gDebounceCounter = 0;
 bool       gWasFKeyPressed  = false;
 
+#ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
+// Short press: hold key for SERIAL_KEY_SHORT_POLLS calls.
+// Must exceed key_debounce_10ms (2) to trigger ProcessKey(key, true, false).
+#define SERIAL_KEY_SHORT_POLLS  5
+
+// Long press: hold key for SERIAL_KEY_LONG_POLLS calls.
+// Must exceed key_repeat_delay_10ms (40) to trigger ProcessKey(key, true, true).
+#define SERIAL_KEY_LONG_POLLS   45
+
+// Packet types for serial key injection (K5Viewer → radio)
+#define SERIAL_KEY_TYPE         0x03
+#define SERIAL_KEY_TYPE_LONG    0x04
+
+volatile KEY_Code_t gKeyFromSerial      = KEY_INVALID;
+static   uint8_t    gSerialKeyHoldCount = 0;
+static   uint8_t    gSerialKeyLong      = 0;  // 0 = short press, 1 = long press
+
+// Inject a short or long press from serial (UART or VCP).
+// KEY_PTT is explicitly blocked — PTT release cannot be guaranteed over serial.
+static inline void KEYBOARD_InjectKey(uint8_t keyCode, bool keyLong)
+{
+    if (keyCode < KEY_INVALID && keyCode != KEY_PTT) {
+        gKeyFromSerial      = (KEY_Code_t)keyCode;
+        gSerialKeyHoldCount = 0;
+        gSerialKeyLong      = keyLong;
+    }
+}
+
+bool KEYBOARD_ProcessProtocolByte(ParseState_t *state, uint8_t b)
+{
+    bool connected = false;
+
+    switch (*state)
+    {
+        case STATE_IDLE:
+            if      (b == 0x55) *state = STATE_KA_1;
+            else if (b == 0xAA) *state = STATE_KEY_1;
+            break;
+            
+        case STATE_KA_1:
+            *state = (b == 0xAA) ? STATE_KA_2 : STATE_IDLE;
+            break;
+            
+        case STATE_KA_2:
+            *state = (b == 0x00) ? STATE_KA_3 : STATE_IDLE;
+            break;
+            
+        case STATE_KA_3:
+            if (b == 0x00) connected = true;
+            *state = STATE_IDLE;
+            break;
+            
+        case STATE_KEY_1:
+            *state = (b == 0x55) ? STATE_KEY_2 : STATE_IDLE;
+            break;
+            
+        case STATE_KEY_2:
+            if      (b == SERIAL_KEY_TYPE)      *state = STATE_KEY_3;
+            else if (b == SERIAL_KEY_TYPE_LONG) *state = STATE_KEY_3L;
+            else                                *state = STATE_IDLE;
+            break;
+            
+        case STATE_KEY_3:
+        case STATE_KEY_3L:
+            KEYBOARD_InjectKey(b, *state == STATE_KEY_3L);
+            connected = true;
+            *state = STATE_IDLE;
+            break;
+
+        default:
+            *state = STATE_IDLE;
+            break;
+    }
+
+    return connected;
+}
+#endif
+
 #define GPIOx               GPIOB
 #define PIN_MASK_COLS       (LL_GPIO_PIN_6 | LL_GPIO_PIN_5 | LL_GPIO_PIN_4 | LL_GPIO_PIN_3)
 #define PIN_COLS            GPIO_MAKE_PIN(GPIOx, PIN_MASK_COLS)
@@ -78,6 +156,25 @@ static const KEY_Code_t keyboard[5][4] = {
 
 KEY_Code_t KEYBOARD_Poll(void)
 {
+#ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
+    // Serial-injected key: hold it for SHORT or LONG polls depending on press type,
+    // so the debounce counter in app.c reaches the right threshold:
+    //   - Short: key_debounce_10ms (2)  → ProcessKey(key, true, false)
+    //   - Long:  key_repeat_delay_10ms (40) → ProcessKey(key, true, true)
+    // Once the hold count is exhausted we clear it — next call returns KEY_INVALID,
+    // which triggers the release path in app.c naturally.
+    if (gKeyFromSerial != KEY_INVALID) {
+        KEY_Code_t injected  = gKeyFromSerial;
+        uint8_t    threshold = gSerialKeyLong ? SERIAL_KEY_LONG_POLLS : SERIAL_KEY_SHORT_POLLS;
+        if (++gSerialKeyHoldCount >= threshold) {
+            gKeyFromSerial      = KEY_INVALID;
+            gSerialKeyHoldCount = 0;
+            gSerialKeyLong      = 0;
+        }
+        return injected;
+    }
+#endif
+
     KEY_Code_t Key = KEY_INVALID;
 
     // Scan all 5 columns - never break early to avoid GPIO state issues
@@ -153,4 +250,19 @@ KEY_Code_t KEYBOARD_Poll(void)
     GPIO_SetOutputPin(PIN_COLS);
 
     return Key;
+}
+
+KEY_Code_t KEYBOARD_GetKey(void)
+{
+    KEY_Code_t btn = KEYBOARD_Poll();
+    if (btn == KEY_INVALID && GPIO_IsPttPressed())
+    {
+        btn = KEY_PTT;
+    }
+    return btn;
+}
+
+void HideFKeyIcon(void) {
+    gWasFKeyPressed       = false;
+    gUpdateStatus         = true;
 }

App/driver/keyboard.h

@@ -45,12 +45,32 @@ enum KEY_Code_e {
 };
 typedef enum KEY_Code_e KEY_Code_t;
 
+typedef enum {
+    STATE_IDLE = 0,
+    STATE_KA_1,
+    STATE_KA_2,
+    STATE_KA_3,
+    STATE_KEY_1,
+    STATE_KEY_2,
+    STATE_KEY_3,
+    STATE_KEY_3L,
+} ParseState_t;
+
 extern KEY_Code_t gKeyReading0;
 extern KEY_Code_t gKeyReading1;
 extern uint16_t   gDebounceCounter;
 extern bool       gWasFKeyPressed;
 
-KEY_Code_t KEYBOARD_Poll(void);
+#ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
+// Serial-injected key (written by UART/VCP parser, consumed by KEYBOARD_Poll).
+extern volatile KEY_Code_t gKeyFromSerial;
 
+bool KEYBOARD_ProcessProtocolByte(ParseState_t *state, uint8_t b);
 #endif
 
+KEY_Code_t KEYBOARD_Poll(void);
+KEY_Code_t KEYBOARD_GetKey(void);
+
+void HideFKeyIcon(void);
+
+#endif

App/driver/py25q16.c

@@ -256,9 +256,9 @@ void PY25Q16_WriteBuffer(uint32_t Address, const void *pBuffer, uint32_t Size, b
     printf("spi flash write: %06x %ld %d\n", Address, Size, Append);
 #endif
 
-    #ifdef ENABLE_FEAT_F4HWN_DEBUG
-        gDebug++;
-    #endif
+    //#ifdef ENABLE_FEAT_F4HWN_DEBUG
+    //    gDebug++;
+    //#endif
 
     uint32_t SecIndex = Address / SECTOR_SIZE;
     uint32_t SecAddr = SecIndex * SECTOR_SIZE;

App/driver/st7565.c

@@ -24,6 +24,7 @@
 #include "driver/st7565.h"
 #include "driver/system.h"
 #include "misc.h"
+#include "screenshot.h"
 
 #define SPIx SPI1
 
@@ -163,6 +164,9 @@ void ST7565_DrawLine(const unsigned int Column, const unsigned int Line, const u
     void ST7565_BlitLine(unsigned line)
     {
         ST7565_BlitScreen(line + 1);
+        #ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
+            SCREENSHOT_Update(true);  // Force immediate capture
+        #endif
     }
 
     void ST7565_BlitStatusLine(void)

App/driver/uart.c

@@ -22,7 +22,10 @@
 #include "py32f071_ll_dma.h"
 #include "py32f071_ll_gpio.h"
 #include "py32f071_ll_usart.h"
-#include "driver/uart.h"
+
+#ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
+#include "driver/keyboard.h"
+#endif
 
 #define USARTx USART1
 #define DMA_CHANNEL LL_DMA_CHANNEL_2
@@ -149,12 +152,26 @@ void UART_LogSend(const void *pBuffer, uint32_t Size)
 
 #ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
     bool UART_IsCableConnected(void) {
-        for (size_t i = 0; i < sizeof(UART_DMA_Buffer); i++) {
-            if (UART_DMA_Buffer[i] == 0x55) {
-                UART_DMA_Buffer[i] = 0x00;  // Clear only the matched byte
-                return true;
-            }
+        static uint8_t     read_ptr = 0;
+        static ParseState_t state   = STATE_IDLE;
+
+        bool connected = false;
+
+        // DMA write position: NbData counts DOWN from 256
+        uint8_t write_ptr = (uint8_t)(sizeof(UART_DMA_Buffer) - 
+                                       LL_DMA_GetDataLength(DMA1, DMA_CHANNEL));
+
+        uint8_t processed = 0;
+        while (read_ptr != write_ptr && processed < sizeof(UART_DMA_Buffer))
+        {
+            uint8_t b = UART_DMA_Buffer[read_ptr++];
+            // read_ptr wraps naturally at 256 since it's uint8_t
+            processed++;
+
+            if(KEYBOARD_ProcessProtocolByte(&state, b))
+                connected = true;
         }
-        return false;
+
+        return connected;
     }
 #endif

App/driver/vcp.c

@@ -18,6 +18,10 @@
 #include "usb_config.h"
 #include "py32f071_ll_bus.h"
 
+#ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
+#include "driver/keyboard.h"
+#endif
+
 uint8_t VCP_RxBuf[VCP_RX_BUF_SIZE];
 volatile uint32_t VCP_RxBufPointer = 0;
 
@@ -38,24 +42,51 @@ void VCP_Init()
     NVIC_EnableIRQ(USBD_IRQn);
 }
 
+#ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
 bool VCP_ScreenshotPing(void)
 {
-    static uint32_t read_ptr = 0;
+    // State machine for parsing incoming packets:
+    //   Keepalive:       0x55 0xAA 0x00 0x00  → viewer alive
+    //   Short key press: 0xAA 0x55 0x03 <key> → inject short press
+    //   Long key press:  0xAA 0x55 0x04 <key> → inject long press
+    //
+    // State transitions:
+    //   IDLE  → 0x55 → KA_1
+    //   KA_1  → 0xAA → KA_2       (else IDLE)
+    //   KA_2  → 0x00 → KA_3       (else IDLE)
+    //   KA_3  → 0x00 → keepalive OK, IDLE
+    //
+    //   IDLE   → 0xAA → KEY_1
+    //   KEY_1  → 0x55 → KEY_2     (else IDLE)
+    //   KEY_2  → 0x03 → KEY_3     (short press, else check long)
+    //   KEY_2  → 0x04 → KEY_3L    (long press, else IDLE)
+    //   KEY_3  → <b>  → KEYBOARD_InjectKey(b, false), IDLE
+    //   KEY_3L → <b>  → KEYBOARD_InjectKey(b, true), IDLE
 
-    uint32_t write_ptr = VCP_RxBufPointer;
+    static uint8_t      read_ptr = 0;
+    static ParseState_t state    = STATE_IDLE;
 
-    while (read_ptr != write_ptr)
+    bool     connected = false;
+    uint8_t  write_ptr = VCP_RxBufPointer;  // snapshot once — ISR may update concurrently
+
+    // Cap bytes processed per call to VCP_RX_BUF_SIZE.
+    // Prevents unbounded loop if the ISR write pointer laps read_ptr
+    // (buffer overflow / corrupted state), which would freeze the firmware.
+    uint32_t processed = 0;
+
+    while (read_ptr != write_ptr && processed < VCP_RX_BUF_SIZE)
     {
         uint8_t b = VCP_RxBuf[read_ptr];
 
         read_ptr++;
         if (read_ptr >= VCP_RX_BUF_SIZE)
             read_ptr = 0;
+        processed++;
 
-        if (b == 0x55)
-        {
-            return true;
-        }
+        if(KEYBOARD_ProcessProtocolByte(&state, b))
+            connected = true;
     }
-    return false;
+
+    return connected;
 }
+#endif // ENABLE_FEAT_F4HWN_SCREENSHOT

App/driver/vcp.h

@@ -28,7 +28,10 @@ extern uint8_t VCP_RxBuf[VCP_RX_BUF_SIZE];
 extern volatile uint32_t VCP_RxBufPointer;
 
 void VCP_Init();
+
+#ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
 bool VCP_ScreenshotPing(void);
+#endif
 
 static inline void VCP_Send(const uint8_t *Buf, uint32_t Size)
 {

App/font.c

@@ -491,7 +491,7 @@ const uint8_t gFontSmall[95-1][6] =
         {0x03, 0x00, 0x03}, //  34 - quotedbl
         {0x1f, 0x0a, 0x1f}, //  35 - numbersign
         {0x0a, 0x1f, 0x05}, //  36 - dollar
-        {0x09, 0x04, 0x12}, //  37 - percent
+        {0x19, 0x04, 0x13}, //  37 - percent
         {0x0f, 0x17, 0x1c}, //  38 - ampersand
         {0x00, 0x03, 0x00}, //  39 - quotesingle
         {0x00, 0x0e, 0x11}, //  40 - parenleft

App/frequencies.c

@@ -163,11 +163,8 @@ int32_t TX_freq_check(const uint32_t Frequency)
 {   // return '0' if TX frequency is allowed
     // otherwise return '-1'
 
-    if (Frequency < frequencyBandTable[0].lower || Frequency > frequencyBandTable[BAND_N_ELEM - 1].upper)
-        return -1;  // not allowed outside this range
-
-    if (Frequency >= BX4819_band1.upper && Frequency < BX4819_band2.lower)
-        return -1;  // BX chip does not work in this range
+    if (RX_freq_check(Frequency))
+        return -1;
 
     switch (gSetting_F_LOCK)
     {
@@ -280,10 +277,10 @@ int32_t RX_freq_check(const uint32_t Frequency)
     // otherwise return '-1'
 
     if (Frequency < frequencyBandTable[0].lower || Frequency > frequencyBandTable[BAND_N_ELEM - 1].upper)
-        return -1;
+        return -1;  // not allowed outside this range
 
     if (Frequency >= BX4819_band1.upper && Frequency < BX4819_band2.lower)
-        return -1;
+        return -1;  // BX chip does not work in this range
 
-    return 0;   // OK frequency
+    return 0;  // OK frequency
 }

App/functions.c

@@ -118,14 +118,7 @@ void FUNCTION_Foreground(const FUNCTION_Type_t PreviousFunction)
 
 void FUNCTION_PowerSave() {
     #ifdef ENABLE_FEAT_F4HWN_SLEEP
-        if(gWakeUp)
-        {
-            gPowerSave_10ms = gEeprom.BATTERY_SAVE * 200; // deep sleep now indexed on BatSav
-        }
-        else
-        {
-            gPowerSave_10ms = gEeprom.BATTERY_SAVE * 10;
-        }
+        gPowerSave_10ms = gEeprom.BATTERY_SAVE * (gWakeUp ? 200 : 10); // deep sleep now indexed on BatSav
     #else
         gPowerSave_10ms = gEeprom.BATTERY_SAVE * 10;
     #endif

App/main.c

@@ -277,77 +277,38 @@ void Main(void)
 #endif
     }
 
-    /*
     #ifdef ENABLE_FEAT_F4HWN_RESUME_STATE
-    if(gEeprom.CURRENT_STATE == 2 || gEeprom.CURRENT_STATE == 5)
-    {
-            gScanRangeStart = gScanRangeStart ? 0 : gTxVfo->pRX->Frequency;
-            gScanRangeStop = gEeprom.VfoInfo[!gEeprom.TX_VFO].freq_config_RX.Frequency;
-            if(gScanRangeStart > gScanRangeStop)
-            {
-                SWAP(gScanRangeStart, gScanRangeStop);
-            }
-    }
-    switch (gEeprom.CURRENT_STATE) {
-        case 1:
-            gEeprom.SCAN_LIST_DEFAULT = gEeprom.CURRENT_LIST;
-            CHFRSCANNER_Start(true, SCAN_FWD);
-            break;
+        if (gEeprom.CURRENT_STATE == 2 || gEeprom.CURRENT_STATE == 5)
+            CHFRSCANNER_ScanRange();
 
-        case 2:
-            CHFRSCANNER_Start(true, SCAN_FWD);
-            break;
+        switch (gEeprom.CURRENT_STATE) {
+            case 1:
+                gEeprom.SCAN_LIST_DEFAULT = gEeprom.CURRENT_LIST;
+                CHFRSCANNER_Start(true, SCAN_FWD);
+                break;
 
-        #ifdef ENABLE_FMRADIO
-        case 3:
-            ACTION_FM();
-            GUI_SelectNextDisplay(gRequestDisplayScreen);
-            break;
-        #endif
+            case 2:
+                CHFRSCANNER_Start(true, SCAN_FWD);
+                break;
 
-        #ifdef ENABLE_SPECTRUM
-        case 4:
-            APP_RunSpectrum();
-            break;
-        case 5:
-            APP_RunSpectrum();
-            break;
-        #endif
+            #ifdef ENABLE_FMRADIO
+                case 3:
+                    ACTION_FM();
+                    GUI_SelectNextDisplay(gRequestDisplayScreen);
+                    break;
+            #endif
 
-        default:
-            // No action for CURRENT_STATE == 0 or other unexpected values
-            break;
-    }
-    #endif
-    */
+            #ifdef ENABLE_SPECTRUM
+                case 4:
+                case 5:
+                    APP_RunSpectrum();
+                    break;
+            #endif
 
-    #ifdef ENABLE_FEAT_F4HWN_RESUME_STATE
-        if (gEeprom.CURRENT_STATE == 2 || gEeprom.CURRENT_STATE == 5) {
-            gScanRangeStart = gScanRangeStart ? 0 : gTxVfo->pRX->Frequency;
-            gScanRangeStop = gEeprom.VfoInfo[!gEeprom.TX_VFO].freq_config_RX.Frequency;
-            if (gScanRangeStart > gScanRangeStop) {
-                SWAP(gScanRangeStart, gScanRangeStop);
-            }
+            default:
+                // No action for CURRENT_STATE == 0 or other unexpected values
+                break;
         }
-
-        if (gEeprom.CURRENT_STATE == 1) {
-            gEeprom.SCAN_LIST_DEFAULT = gEeprom.CURRENT_LIST;
-        }
-
-        if (gEeprom.CURRENT_STATE == 1 || gEeprom.CURRENT_STATE == 2) {
-            CHFRSCANNER_Start(true, SCAN_FWD);
-        }
-        #ifdef ENABLE_FMRADIO
-        else if (gEeprom.CURRENT_STATE == 3) {
-            ACTION_FM();
-            GUI_SelectNextDisplay(gRequestDisplayScreen);
-        }
-        #endif
-        #ifdef ENABLE_SPECTRUM
-        else if (gEeprom.CURRENT_STATE == 4 || gEeprom.CURRENT_STATE == 5) {
-            APP_RunSpectrum();
-        }
-        #endif
     #endif
         
     while (true) {

App/misc.c

@@ -87,7 +87,7 @@ const uint16_t    NOAA_countdown_3_10ms            =   200 / 10;   // 200ms
 
 const uint32_t    gDefaultAesKey[4]                = {0x4AA5CC60, 0x0312CC5F, 0xFFD2DABB, 0x6BBA7F92};
 
-const uint8_t     gMicGain_dB2[5]                  = {3, 8, 16, 24, 31};
+const uint8_t     gMicGain_dB2[9]                  = {3, 8, 16, 24, 32, 40, 48, 56, 63}; // BK4819 {3, 8, 16, 24, 31};
 
 #ifndef ENABLE_FEAT_F4HWN
     bool              gSetting_350TX;
@@ -135,7 +135,7 @@ enum BacklightOnRxTx_t gSetting_backlight_on_tx_rx;
     bool          gSetting_set_tmr = 0;
     bool          gSetting_set_ptt_session;
     #ifdef ENABLE_FEAT_F4HWN_DEBUG
-        uint16_t       gDebug;
+        int16_t   gDebug;
     #endif
     uint8_t       gDW = 0;
     uint8_t       gCB = 0;
@@ -149,6 +149,7 @@ enum BacklightOnRxTx_t gSetting_backlight_on_tx_rx;
         bool          gPowerHigh = false;
         bool          gRemoveOffset = false;
     #endif
+    int8_t dBmCorrTable[7] = {-15, -16, -10, -4, -7, -6, -1};
 #endif
 
 #ifdef ENABLE_AUDIO_BAR
@@ -241,6 +242,7 @@ volatile uint16_t gScanPauseDelayIn_10ms;
 uint16_t          gMenuCountdown;
 bool              gPttWasReleased;
 bool              gPttWasPressed;
+bool              gHasVfoBackup;
 uint8_t           gKeypadLocked;
 bool              gFlagReconfigureVfos;
 uint8_t           gVfoConfigureMode;
@@ -248,6 +250,7 @@ bool              gFlagResetVfos;
 bool              gRequestSaveVFO;
 uint16_t          gRequestSaveChannel;
 bool              gRequestSaveSettings;
+bool              gRequestSaveSquelch;
 #ifdef ENABLE_FMRADIO
     bool          gRequestSaveFM;
 #endif
@@ -292,7 +295,7 @@ uint8_t           gFSKWriteIndex;
 
 #ifdef ENABLE_NOAA
     bool          gIsNoaaMode;
-    uint16_t      gNoaaChannel;
+    uint8_t      gNoaaChannel;
 #endif
 
 bool              gUpdateDisplay;
@@ -334,6 +337,7 @@ uint8_t           gIsLocked = 0xFF;
     uint16_t gVfoSaveCountdown_10ms = 0;
     bool gScheduleVfoSave = false;
     bool gVfoStateChanged = false;
+    char    gListName[MR_CHANNELS_LIST][4];
 #endif
 
 inline void FUNCTION_NOP() { ; }
@@ -632,4 +636,16 @@ void MR_PrintCacheStats(void)
     //    cache_hits, cache_misses, MR_GetCacheHitRate());
 }
 
+#endif
+
+#ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
+    bool SCREENSHOT_IsLocked(void) 
+    {
+        if (gUART_LockScreenshot > 0) {
+            gUART_LockScreenshot--;
+            return true;
+        }
+        
+        return false;
+    }
 #endif

App/misc.h

@@ -148,7 +148,7 @@ extern const uint16_t        scan_pause_delay_in_7_10ms;
 //extern const uint16_t        gMax_bat_v;
 //extern const uint16_t        gMin_bat_v;
 
-extern const uint8_t         gMicGain_dB2[5];
+extern const uint8_t         gMicGain_dB2[9];
 
 #ifndef ENABLE_FEAT_F4HWN
 extern bool                  gSetting_350TX;
@@ -197,7 +197,7 @@ extern enum BacklightOnRxTx_t gSetting_backlight_on_tx_rx;
     extern bool               gSetting_set_tmr;
     extern bool               gSetting_set_ptt_session;
     #ifdef ENABLE_FEAT_F4HWN_DEBUG
-        extern uint16_t            gDebug;
+        extern int16_t        gDebug;
     #endif
     extern uint8_t            gDW;
     extern uint8_t            gCB;
@@ -211,6 +211,7 @@ extern enum BacklightOnRxTx_t gSetting_backlight_on_tx_rx;
         extern bool               gPowerHigh;
         extern bool               gRemoveOffset;
     #endif
+    extern int8_t dBmCorrTable[7];
 #endif
 
 #ifdef ENABLE_AUDIO_BAR
@@ -322,6 +323,8 @@ extern volatile bool         gTxTimeoutReached;
     #ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
         extern volatile uint8_t  gUART_LockScreenshot; // lock screenshot if Chirp is used
         extern bool gUSB_ScreenshotEnabled;
+
+        bool SCREENSHOT_IsLocked(void);
     #endif
 #endif
 
@@ -365,12 +368,14 @@ extern AlarmState_t          gAlarmState;
 extern uint16_t              gMenuCountdown;
 extern bool                  gPttWasReleased;
 extern bool                  gPttWasPressed;
+extern bool                  gHasVfoBackup;
 extern bool                  gFlagReconfigureVfos;
 extern uint8_t               gVfoConfigureMode;
 extern bool                  gFlagResetVfos;
 extern bool                  gRequestSaveVFO;
 extern uint16_t              gRequestSaveChannel;
 extern bool                  gRequestSaveSettings;
+extern bool                  gRequestSaveSquelch;
 #ifdef ENABLE_FMRADIO
     extern bool              gRequestSaveFM;
 #endif
@@ -455,6 +460,8 @@ extern volatile uint8_t      boot_counter_10ms;
     extern uint16_t gVfoSaveCountdown_10ms;
     extern bool gScheduleVfoSave;
     extern bool gVfoStateChanged;
+
+    extern char gListName[MR_CHANNELS_LIST][4];
 #endif
 
 int32_t NUMBER_AddWithWraparound(int32_t Base, int32_t Add, int32_t LowerLimit, int32_t UpperLimit);

App/radio.c

@@ -102,28 +102,30 @@ bool RADIO_CheckValidList(uint8_t scanList)
     return false;
 }
 
-void RADIO_NextValidList(void)
+void RADIO_NextValidList(int8_t direction)
 {
     uint8_t startList = gEeprom.SCAN_LIST_DEFAULT;
     uint8_t attempts = 0;
-    const uint8_t MAX_LISTS = MR_CHANNELS_LIST + 2;  // 1-25, includes ALL
+    const uint8_t MAX_VALUE = MR_CHANNELS_LIST + 1;  // 25 (1-24 lists + ALL)
     
     do {
-        // Move to next scan list, wrapping around from 25 to 1
-        gEeprom.SCAN_LIST_DEFAULT = ((gEeprom.SCAN_LIST_DEFAULT + 1) % MAX_LISTS) ?: 1;
+        if (direction > 0) {
+            // Forward: 1 → 2 → ... → 25 → 1
+            gEeprom.SCAN_LIST_DEFAULT = (gEeprom.SCAN_LIST_DEFAULT % MAX_VALUE) + 1;
+        } else {
+            // Backward: 25 → 24 → ... → 1 → 25
+            gEeprom.SCAN_LIST_DEFAULT = ((gEeprom.SCAN_LIST_DEFAULT - 2 + MAX_VALUE) % MAX_VALUE) + 1;
+        }
         attempts++;
         
-        // Check if current list has valid channels
         if (RADIO_CheckValidList(gEeprom.SCAN_LIST_DEFAULT))
             return;
             
-    // Stop if we've cycled through all lists or made too many attempts
-    } while (gEeprom.SCAN_LIST_DEFAULT != startList && attempts < MAX_LISTS);
+    } while (gEeprom.SCAN_LIST_DEFAULT != startList && attempts < MAX_VALUE);
     
-    // Safety fallback: if no valid list found, switch to ALL mode
-    // This prevents infinite loops and ensures scanning can continue
+    // Safety fallback: switch to ALL mode
     if (!RADIO_CheckValidList(gEeprom.SCAN_LIST_DEFAULT)) {
-        gEeprom.SCAN_LIST_DEFAULT = MR_CHANNELS_LIST + 1;  // ALL
+        gEeprom.SCAN_LIST_DEFAULT = MAX_VALUE;  // ALL (25)
     }
 }
 
@@ -794,8 +796,8 @@ void RADIO_SetupRegisters(bool switchToForeground)
     }
     BK4819_WriteRegister(BK4819_REG_3F, 0);
 
-    // mic gain 0.5dB/step 0 to 31
-    BK4819_WriteRegister(BK4819_REG_7D, 0xE940 | (gEeprom.MIC_SENSITIVITY_TUNING & 0x1f));
+    // mic gain 0.5dB/step 0 to 63
+    BK4819_WriteRegister(BK4819_REG_7D, 0xE940 | (gEeprom.MIC_SENSITIVITY_TUNING & 0x3f));
 
     uint32_t Frequency;
     #ifdef ENABLE_NOAA
@@ -924,8 +926,8 @@ void RADIO_SetupRegisters(bool switchToForeground)
     BK4819_EnableDTMF();
     InterruptMask |= BK4819_REG_3F_DTMF_5TONE_FOUND;
 
-    //RADIO_SetupAGC(gRxVfo->Modulation == MODULATION_AM, false);
-    RADIO_SetupAGC(false, false);
+    RADIO_SetupAGC(gRxVfo->Modulation == MODULATION_AM, false);
+    //RADIO_SetupAGC(false, false);
 
     // enable/disable BK4819 selected interrupts
     BK4819_WriteRegister(BK4819_REG_3F, InterruptMask);
@@ -1054,6 +1056,31 @@ void RADIO_SetTxParameters(void)
 
 void RADIO_SetModulation(ModulationMode_t modulation)
 {
+    #ifdef ENABLE_BYP_RAW_DEMODULATORS
+    // BYP on BK4829 uses full audio bypass profile.
+    if (modulation == MODULATION_BYP) {
+        BK4819_EnterBypass();
+        BK4819_SetRegValue(afDacGainRegSpec, 0xF);
+        BK4819_WriteRegister(BK4819_REG_3D, 0x2AAB);
+        RADIO_SetupAGC(false, false);
+        return;
+    }
+
+    // RAW on BK4829 uses RX-only filter bypass profile.
+    if (modulation == MODULATION_RAW) {
+        BK4819_EnterRaw();
+        BK4819_SetRegValue(afDacGainRegSpec, 0xF);
+        BK4819_WriteRegister(BK4819_REG_3D, 0x0000);
+        RADIO_SetupAGC(false, false);
+        return;
+    }
+    #endif
+
+    #ifdef ENABLE_BYP_RAW_DEMODULATORS
+    // Ensure we always leave bypass / raw mode before applying normal modulation settings.
+    BK4819_ExitBypass();
+    #endif
+
     BK4819_AF_Type_t mod;
     switch(modulation) {
         default:
@@ -1067,14 +1094,6 @@ void RADIO_SetModulation(ModulationMode_t modulation)
             mod = BK4819_AF_BASEBAND2;
             break;
 
-#ifdef ENABLE_BYP_RAW_DEMODULATORS
-        case MODULATION_BYP:
-            mod = BK4819_AF_UNKNOWN3;
-            break;
-        case MODULATION_RAW:
-            mod = BK4819_AF_BASEBAND1;
-            break;
-#endif
     }
 
     BK4819_SetAF(mod);
@@ -1109,13 +1128,16 @@ void RADIO_SetModulation(ModulationMode_t modulation)
         BK4819_WriteRegister(0x31,uVar1 | 1);
         BK4819_WriteRegister(0x42,0x6f5c);
         BK4819_WriteRegister(0x2a,0x7434);
-        BK4819_WriteRegister(0x2b,0x300);
+        BK4819_WriteRegister(0x2b,0x400);
         BK4819_WriteRegister(0x2f,0x9990);
         //BK4819_WriteRegister(0x54, 0x9775);
         //BK4819_WriteRegister(0x55, 0x32c6);
 
-        BK4819_WriteRegister(0x54, 0x8846);
-        BK4819_WriteRegister(0x55, 0x38C0);
+        //BK4819_WriteRegister(0x54, 0x8846);
+        //BK4819_WriteRegister(0x55, 0x38C0);
+
+        BK4819_WriteRegister(0x54, 0x9009);
+        BK4819_WriteRegister(0x55, 0x31a9);
 
         BK4819_SetFilterBandwidth(BK4819_FILTER_BW_AM, true);
     }
@@ -1124,36 +1146,28 @@ void RADIO_SetModulation(ModulationMode_t modulation)
     BK4819_WriteRegister(BK4819_REG_3D, modulation == MODULATION_USB ? 0 : 0x2AAB);
     BK4819_SetRegValue(afcDisableRegSpec, modulation != MODULATION_FM);
 
-    //RADIO_SetupAGC(modulation == MODULATION_AM, false);
-    RADIO_SetupAGC(false, false);
+    RADIO_SetupAGC(modulation == MODULATION_AM, false);
+    //RADIO_SetupAGC(false, false);
 }
 
 void RADIO_SetupAGC(bool listeningAM, bool disable)
 {
-    static uint8_t lastSettings;
+    static uint8_t lastSettings = 0xFF;
     uint8_t newSettings = (listeningAM << 1) | disable;
-    if(lastSettings == newSettings)
+    if (lastSettings == newSettings)
         return;
     lastSettings = newSettings;
 
-
-    if(!listeningAM) { // if not actively listening AM we don't need any AM specific regulation
-        BK4819_SetAGC(!disable);
-        BK4819_InitAGC(false);
-    }
-    else {
 #ifdef ENABLE_AM_FIX
-        if(gSetting_AM_fix) { // if AM fix active lock AGC so AM-fix can do it's job
-            BK4819_SetAGC(0);
-            AM_fix_enable(!disable);
-        }
-        else
-#endif
-        {
-            BK4819_SetAGC(!disable);
-            BK4819_InitAGC(true);
-        }
+    if (listeningAM && gSetting_AM_fix) {
+        BK4819_SetAGC(0);
+        AM_fix_enable(!disable);
+        return;
     }
+#endif
+
+    BK4819_SetAGC(!disable);
+    BK4819_InitAGC(listeningAM);
 }
 
 void RADIO_SetVfoState(VfoState_t State)
@@ -1227,6 +1241,12 @@ void RADIO_PrepareTX(void)
         // over voltage .. this is being a pain
         State = VFO_STATE_VOLTAGE_HIGH;
     }
+#ifdef ENABLE_BYP_RAW_DEMODULATORS
+    else if (gCurrentVfo->Modulation == MODULATION_BYP || gCurrentVfo->Modulation == MODULATION_RAW) {
+        // BYP/RAW are receive-only modes.
+        State = VFO_STATE_TX_DISABLE;
+    }
+#endif
 #ifndef ENABLE_TX_WHEN_AM
     else if (gCurrentVfo->Modulation != MODULATION_FM) {
         // not allowed to TX if in AM mode

App/radio.h

@@ -149,7 +149,7 @@ extern DCS_CodeType_t gCurrentCodeType;
 extern VfoState_t     VfoState[2];
 
 bool     RADIO_CheckValidList(uint8_t scanList);
-void     RADIO_NextValidList(void);
+void     RADIO_NextValidList(int8_t direction);
 bool     RADIO_CheckValidChannel(uint16_t channel, bool checkScanList, uint8_t scanList);
 uint16_t RADIO_FindNextChannel(uint16_t ChNum, int8_t Direction, bool bCheckScanList, uint8_t RadioNum);
 void     RADIO_InitInfo(VFO_Info_t *pInfo, const uint16_t ChannelSave, const uint32_t Frequency);

App/screenshot.c

@@ -19,8 +19,31 @@
 #include "screenshot.h"
 #include "misc.h"
 #include "driver/vcp.h"
+#include "driver/keyboard.h"
 
-static void Screenshot_Send(const uint8_t *buf, uint16_t len)
+// SRAM optimization: minimize static allocations
+// - previousFrame: 1024 bytes (REQUIRED - need to compare for delta)
+// - No currentFrame or deltaFrame static buffers
+static uint8_t previousFrame[1024] = {0};
+static uint8_t forcedBlock = 0;
+static uint8_t keepAlive = 3;
+
+void SCREENSHOT_ParseInput(void)
+{
+    if (SCREENSHOT_IsLocked())
+        return;
+
+    if (UART_IsCableConnected()) {
+        keepAlive = 15;
+        gUSB_ScreenshotEnabled = false;
+    }
+    else if (VCP_ScreenshotPing()) {
+        keepAlive = 15;
+        gUSB_ScreenshotEnabled = true;
+    }
+}
+
+static void SCREENSHOT_Send(const uint8_t *buf, uint16_t len)
 {
     if (gUSB_ScreenshotEnabled) {
         cdc_acm_data_send_with_dtr(buf, len);
@@ -29,14 +52,19 @@ static void Screenshot_Send(const uint8_t *buf, uint16_t len)
     }
 }
 
-// SRAM optimization: minimize static allocations
-// - previousFrame: 1024 bytes (REQUIRED - need to compare for delta)
-// - No currentFrame or deltaFrame static buffers
-static uint8_t previousFrame[1024] = {0};
-static uint8_t forcedBlock = 0;
-static uint8_t keepAlive = 10;
+void SCREENSHOT_Line(uint8_t *src, uint8_t *dest, uint16_t *idx) {
+    for (uint8_t b = 0; b < 8; b++) {
+        for (uint8_t i = 0; i < 128; i += 8) {
+            uint8_t acc = 0;
+            for (uint8_t k = 0; k < 8; k++) {
+                if (src[i + k] & (1 << b)) acc |= (1 << k);
+            }
+            dest[(*idx)++] = gSetting_set_inv ? ~acc : acc;
+        }
+    }
+}
 
-void getScreenShot(bool force)
+void SCREENSHOT_Update(bool force)
 {
     // Build frame in a temporary stack buffer
     // This is 1024 bytes but it's temporary and gets freed after the function
@@ -44,55 +72,34 @@ void getScreenShot(bool force)
     uint16_t index = 0;
     uint8_t acc = 0;
     uint8_t bitCount = 0;
+    static bool wasConnected = false;
 
-    if (gUART_LockScreenshot > 0) {
-        gUART_LockScreenshot--;
+    if (SCREENSHOT_IsLocked())
         return;
-    }
-
-    if (UART_IsCableConnected()) {
-        keepAlive = 10;
-        gUSB_ScreenshotEnabled = false;
-    }
-
-    if (VCP_ScreenshotPing()) {
-        keepAlive = 10;
-        gUSB_ScreenshotEnabled = true;
-    }
 
     if (keepAlive > 0) {
-        if (--keepAlive == 0) return;
+        if (--keepAlive == 0) {
+            // Connection just lost → reset state for next reconnection
+            wasConnected = false;
+            return;
+        }
     } else {
         return;
     }
 
+    // Connection is alive — detect reconnection and force full frame
+    if (!wasConnected) {
+        force = true;
+        wasConnected = true;
+    }
+
     // ==== BUILD FRAME ONCE ====
     // Status line: 8 bit layers × 128 columns
-    for (uint8_t b = 0; b < 8; b++) {
-        for (uint8_t i = 0; i < 128; i++) {
-            uint8_t bit = (gStatusLine[i] >> b) & 0x01;
-            acc |= (bit << bitCount++);
-            if (bitCount == 8) {
-                frameBuffer[index++] = acc;
-                acc = 0;
-                bitCount = 0;
-            }
-        }
-    }
+    SCREENSHOT_Line(gStatusLine, frameBuffer, &index);
 
     // Frame buffer: 7 lines × 8 bit layers × 128 columns
     for (uint8_t l = 0; l < 7; l++) {
-        for (uint8_t b = 0; b < 8; b++) {
-            for (uint8_t i = 0; i < 128; i++) {
-                uint8_t bit = (gFrameBuffer[l][i] >> b) & 0x01;
-                acc |= (bit << bitCount++);
-                if (bitCount == 8) {
-                    frameBuffer[index++] = acc;
-                    acc = 0;
-                    bitCount = 0;
-                }
-            }
-        }
+        SCREENSHOT_Line(gFrameBuffer[l], frameBuffer, &index);
     }
 
     if (bitCount > 0)
@@ -125,11 +132,16 @@ void getScreenShot(bool force)
     if (deltaLen == 0)
         return;
 
+    // Skip transmission if a key is currently pressed
+    // UART_Send is blocking - would freeze the main loop and lose keypresses
+    if (gKeyReading0 != KEY_INVALID)
+        return;
+
     // ==== Send version marker (for backward compatibility detection) ====
     // New format: sends 0xFF before header
     // Old format: doesn't exist, so viewers can differentiate
     uint8_t versionMarker = 0xFF;
-    Screenshot_Send(&versionMarker, 1);
+    SCREENSHOT_Send(&versionMarker, 1);
 
     // ==== Send header ====
     uint8_t header[5] = {
@@ -138,7 +150,7 @@ void getScreenShot(bool force)
         (uint8_t)(deltaLen & 0xFF)
     };
 
-    Screenshot_Send(header, 5);
+    SCREENSHOT_Send(header, 5);
 
     // ==== SECOND PASS: Send only changed chunks ====
     uint8_t chunk[9];
@@ -151,12 +163,12 @@ void getScreenShot(bool force)
         chunk[0] = chunkIdx;
         memcpy(&chunk[1], cur, 8);
         
-        Screenshot_Send(chunk, 9);
+        SCREENSHOT_Send(chunk, 9);
         
         // Update previousFrame for next comparison
         memcpy(prev, cur, 8);
     }
 
     uint8_t end = 0x0A;
-    Screenshot_Send(&end, 1);
+    SCREENSHOT_Send(&end, 1);
 }

App/screenshot.h

@@ -17,6 +17,7 @@
 #ifndef SCREENSHOT_H
 #define SCREENSHOT_H
 
-void getScreenShot(bool force);
+void SCREENSHOT_Update(bool force);
+void SCREENSHOT_ParseInput(void);
 
 #endif

App/settings.c

@@ -59,7 +59,7 @@ void SETTINGS_InitEEPROM(void)
             configByte[4] &= (uint8_t)~0x01;  // KEY_LOCK = 0
             configByte[4] &= (uint8_t)~0x02;  // MENU_LOCK = 0
             configByte[4] &= (uint8_t)~0x3C;  // SET_KEY = 0
-            configByte[4] &= (uint8_t)~0x40;  // SET_NAV = 0
+            //configByte[4] &= (uint8_t)~0x40;  // SET_NAV = 0
 
             PY25Q16_WriteBuffer(0x00A000, configByte, sizeof(configByte), false);
 
@@ -97,6 +97,24 @@ void SETTINGS_InitEEPROM(void)
             if (needsWrite) {
                 PY25Q16_WriteBuffer(0x00A0C8, logoLines, sizeof(logoLines), false);
             }
+
+            // 5. Reset dBmCorrTable
+            int8_t buf[7];
+            PY25Q16_ReadBuffer(0x00A0B9, (uint8_t *)buf, 7);
+
+            needsWrite = true;
+            for (uint8_t i = 0; i < 7; i++) {
+                if ((uint8_t)buf[i] != 0xFF) {
+                    needsWrite = false;
+                    break;
+                }
+            }
+
+            if (needsWrite) {
+                for (uint8_t i = 0; i < 7; i++)
+                    buf[i] = dBmCorrTable[i];
+                PY25Q16_WriteBuffer(0x00A0B9, buf, 7, false);
+            }
         }
     }
 
@@ -122,7 +140,7 @@ void SETTINGS_InitEEPROM(void)
         gEeprom.VOX_SWITCH       = (Data[5] <  2) ? Data[5] : false;
         gEeprom.VOX_LEVEL        = (Data[6] < 10) ? Data[6] : 1;
     #endif
-    gEeprom.MIC_SENSITIVITY      = (Data[7] <  5) ? Data[7] : 4;
+    gEeprom.MIC_SENSITIVITY      = (Data[7] <  9) ? Data[7] : 4;
 
     // 0E78..0E7F
     PY25Q16_ReadBuffer(0x00A008, Data, 8);
@@ -240,13 +258,10 @@ gEeprom.FreqChannel[1]   = IS_FREQ_CHANNEL(Data16[5]) ? Data16[5] : (FREQ_CHANNE
     gEeprom.VOICE_PROMPT = (Data[0] < 3) ? Data[0] : VOICE_PROMPT_ENGLISH;
     #endif
     #ifdef ENABLE_RSSI_BAR
-        if((Data[1] < 200 && Data[1] > 90) && (Data[2] < Data[1]-9 && Data[1] < 160  && Data[2] > 50)) {
-            gEeprom.S0_LEVEL = Data[1];
-            gEeprom.S9_LEVEL = Data[2];
-        }
-        else {
-            gEeprom.S0_LEVEL = 130;
-            gEeprom.S9_LEVEL = 76;
+        for (uint8_t i = 0; i < 7; i++) {
+            int8_t val = (int8_t)Data[i + 1];
+            if (val >= -64 && val <= 64)
+                dBmCorrTable[i] = val;
         }
     #endif
 
@@ -403,6 +418,9 @@ gEeprom.FreqChannel[1]   = IS_FREQ_CHANNEL(Data16[5]) ? Data16[5] : (FREQ_CHANNE
     }
     */
 
+    // Init list name
+    PY25Q16_ReadBuffer(0x00880E, gListName, sizeof(gListName));
+
     // Init attr cache
     MR_InitChannelAttributesCache();
 
@@ -599,15 +617,20 @@ void SETTINGS_FetchChannelName(char *s, const uint16_t channel)
 
 void SETTINGS_FactoryReset(bool bIsAll)
 {
-    PY25Q16_SectorErase(0x000000);
-    PY25Q16_SectorErase(0x001000);
-    PY25Q16_SectorErase(0x003000);
-    PY25Q16_SectorErase(0x004000);
-    PY25Q16_SectorErase(0x005000);
-    PY25Q16_SectorErase(0x006000);
-    PY25Q16_SectorErase(0x007000);
-    PY25Q16_SectorErase(0x008000);
-    PY25Q16_SectorErase(0x009000);
+    // PY25Q16_SectorErase(0x000000);
+    // PY25Q16_SectorErase(0x001000);
+    // PY25Q16_SectorErase(0x002000);
+    // PY25Q16_SectorErase(0x003000);
+    // PY25Q16_SectorErase(0x004000);
+    // PY25Q16_SectorErase(0x005000);
+    // PY25Q16_SectorErase(0x006000);
+    // PY25Q16_SectorErase(0x007000);
+    // PY25Q16_SectorErase(0x008000);
+    // PY25Q16_SectorErase(0x009000);
+
+    for (uint32_t addr = 0x000000; addr <= 0x009000; addr += 0x1000) {
+        PY25Q16_SectorErase(addr);
+    }
     
     // 0d60 - 0e30
     if (bIsAll)
@@ -743,7 +766,10 @@ void SETTINGS_SaveSettings(void)
     #ifdef ENABLE_FEAT_F4HWN_AUDIO
         State[0] = gSetting_set_audio;
     #endif
-    State[1] = gEeprom.SQUELCH_LEVEL;
+    if (gRequestSaveSquelch)
+    {
+        State[1] = gEeprom.SQUELCH_LEVEL;
+    }
     State[2] = gEeprom.TX_TIMEOUT_TIMER;
     #ifdef ENABLE_NOAA
         State[3] = gEeprom.NOAA_AUTO_SCAN;
@@ -1105,7 +1131,7 @@ void SETTINGS_UpdateChannel(uint16_t channel, const VFO_Info_t *pVFO, bool keep,
             };        // default attributes
 
         // 0x0D60
-        PY25Q16_ReadBuffer(0x008000 + channel, &state, 1);
+        PY25Q16_ReadBuffer(0x008000 + (channel * 2), &state, 2);
 
         if (keep) {
             att.band = pVFO->Band;

App/ui/fmradio.c

@@ -35,6 +35,10 @@ void UI_DisplayFM(void)
     char *pPrintStr = String;
     UI_DisplayClear();
 
+#ifdef ENABLE_FEAT_F4HWN
+    UI_DisplayUnlockKeyboard(5);
+#endif
+
     UI_PrintString("FM", 2, 0, 0, 8);
 
     sprintf(String, "%d%s-%dM", 

App/ui/helper.c

@@ -22,6 +22,7 @@
 #include "ui/helper.h"
 #include "ui/inputbox.h"
 #include "misc.h"
+#include "settings.h"
 
 
 void UI_GenerateChannelString(char *pString, const uint16_t Channel)
@@ -44,23 +45,23 @@ void UI_GenerateChannelString(char *pString, const uint16_t Channel)
 void UI_GenerateChannelStringEx(char *pString, const bool bShowPrefix, const uint16_t ChannelNumber)
 {
     if (gInputBoxIndex > 0) {
-        for (unsigned int i = 0; i < 3; i++) {
+        for (unsigned int i = 0; i < 4; i++) {
             pString[i] = (gInputBox[i] == 10) ? '-' : gInputBox[i] + '0';
         }
 
-        pString[3] = 0;
+        pString[4] = 0;
         return;
     }
 
     if (bShowPrefix) {
         // BUG here? Prefixed NULLs are allowed
-        sprintf(pString, "CH-%03u", ChannelNumber + 1);
+        sprintf(pString, "CH-%04u", ChannelNumber + 1);
     } else if (ChannelNumber == MR_CHANNEL_LAST + 1) {
         strcpy(pString, "None");
     } else if (ChannelNumber == 0xFFFF) {
         strcpy(pString, "NULL");
     } else {
-        sprintf(pString, "%03u", ChannelNumber + 1);
+        sprintf(pString, "%04u", ChannelNumber + 1);
     }
 }
 
@@ -130,17 +131,17 @@ void UI_PrintStringSmallNormalInverse(const char *pString, uint8_t Start, uint8_
     if (End != 0 && x_end > End)
         x_end = End;
 
-    gFrameBuffer[Line][x_start - 3] ^= 0x3E;
-    gFrameBuffer[Line][x_start - 2] ^= 0x7F;
-    gFrameBuffer[Line][x_start - 1] ^= 0xFF;
+    //gFrameBuffer[Line][x_start - 2] ^= 0x3E;
+    gFrameBuffer[Line][x_start - 1] ^= 0x7F;
+    //gFrameBuffer[Line][x_start - 1] ^= 0xFF;
     for (uint8_t x = x_start; x < x_end; x++)
     {
         gFrameBuffer[Line][x] ^= 0xFF;
         gFrameBuffer[Line - 1][x] ^= 0x80;
     }
-    gFrameBuffer[Line][x_end + 0] ^= 0xFF;
-    gFrameBuffer[Line][x_end + 1] ^= 0x7F;
-    gFrameBuffer[Line][x_end + 2] ^= 0x3E;
+    //gFrameBuffer[Line][x_end + 0] ^= 0xFF;
+    gFrameBuffer[Line][x_end + 0] ^= 0x7F;
+    //gFrameBuffer[Line][x_end + 1] ^= 0x3E;
 }
 
 
@@ -157,30 +158,6 @@ void UI_PrintStringSmallBold(const char *pString, uint8_t Start, uint8_t End, ui
     UI_PrintStringSmall(pString, Start, End, Line, char_width, font);
 }
 
-void UI_PrintStringSmallBoldInverse(const char *pString, uint8_t Start, uint8_t End, uint8_t Line)
-{
-    // First draw the string normally
-    UI_PrintStringSmallBold(pString, Start, End, Line);
-
-    // Now invert the framebuffer bits for the rendered area
-    uint8_t len = strlen(pString);
-    uint8_t char_width = 7; // small font is typically 6px wide
-
-    uint8_t x_start = Start;
-    uint8_t x_end   = Start + (len * char_width);
-
-    if (End != 0 && x_end > End)
-        x_end = End;
-
-    gFrameBuffer[Line][x_start] ^= 0x7F;
-    for (uint8_t x = x_start + 1; x < x_end; x++)
-    {
-        gFrameBuffer[Line][x] ^= 0x41;
-    }
-    gFrameBuffer[Line][x_end + 1] ^= 0x7F;
-}
-
-
 void UI_PrintStringSmallBufferNormal(const char *pString, uint8_t * buffer)
 {
     UI_PrintStringBuffer(pString, buffer, ARRAY_SIZE(gFontSmall[0]), (uint8_t *)gFontSmall);
@@ -345,6 +322,33 @@ static void sort(int16_t *a, int16_t *b)
         x += 4;
       }
     }
+
+    void UI_DisplayUnlockKeyboard(uint8_t shift) {
+        if (gEeprom.KEY_LOCK && gKeypadLocked > 0)
+        {   // tell user how to unlock the keyboard
+            
+            //memcpy(gFrameBuffer[shift] + 2, gFontKeyLock, sizeof(gFontKeyLock));
+            UI_PrintStringSmallBold("UNLOCK KEYBOARD", 12, 0, shift);
+            //memcpy(gFrameBuffer[shift] + 120, gFontKeyLock, sizeof(gFontKeyLock));
+
+            /*
+            for (uint8_t i = 12; i < 116; i++)
+            {
+                gFrameBuffer[shift][i] ^= 0xFF;
+            }
+            */
+        }
+    }
+
+    bool IsEmptyName(const char *name, uint8_t len) {
+        if (name[0] == '\0' || name[0] == '\xff')
+            return true;
+        for (uint8_t i = 0; i < len; i++) {
+            if (name[i] != ' ' && name[i] != '\xff' && name[i] != '\0')
+                return false;
+        }
+        return true;
+    }
 #endif
     
 void UI_DrawLineBuffer(uint8_t (*buffer)[128], int16_t x1, int16_t y1, int16_t x2, int16_t y2, bool black)

App/ui/helper.h

@@ -26,7 +26,6 @@ void UI_PrintString(const char *pString, uint8_t Start, uint8_t End, uint8_t Lin
 void UI_PrintStringSmallNormal(const char *pString, uint8_t Start, uint8_t End, uint8_t Line);
 void UI_PrintStringSmallNormalInverse(const char *pString, uint8_t Start, uint8_t End, uint8_t Line);
 void UI_PrintStringSmallBold(const char *pString, uint8_t Start, uint8_t End, uint8_t Line);
-void UI_PrintStringSmallBoldInverse(const char *pString, uint8_t Start, uint8_t End, uint8_t Line);
 void UI_PrintStringSmallBufferNormal(const char *pString, uint8_t *buffer);
 void UI_PrintStringSmallBufferBold(const char *pString, uint8_t * buffer);
 void UI_DisplayFrequency(const char *string, uint8_t X, uint8_t Y, bool center);
@@ -39,6 +38,8 @@ void UI_DrawPixelBuffer(uint8_t (*buffer)[128], uint8_t x, uint8_t y, bool black
     void PutPixel(uint8_t x, uint8_t y, bool fill);
     void PutPixelStatus(uint8_t x, uint8_t y, bool fill);
     void GUI_DisplaySmallest(const char *pString, uint8_t x, uint8_t y, bool statusbar, bool fill);
+    void UI_DisplayUnlockKeyboard(uint8_t shift);
+    bool IsEmptyName(const char *name, uint8_t len);
 #endif
 void UI_DrawLineBuffer(uint8_t (*buffer)[128], int16_t x1, int16_t y1, int16_t x2, int16_t y2, bool black);
 void UI_DrawRectangleBuffer(uint8_t (*buffer)[128], int16_t x1, int16_t y1, int16_t x2, int16_t y2, bool black);

App/ui/main.c

@@ -46,7 +46,7 @@
 center_line_t center_line = CENTER_LINE_NONE;
 
 #ifdef ENABLE_FEAT_F4HWN
-    static int8_t RxBlink;
+    // static int8_t RxBlink;
     static int8_t RxBlinkLed = 0;
     static int8_t RxBlinkLedCounter;
     static int8_t RxLine;
@@ -60,16 +60,6 @@ center_line_t center_line = CENTER_LINE_NONE;
     }
 #endif
 
-const int8_t dBmCorrTable[7] = {
-            -15, // band 1
-            -25, // band 2
-            -20, // band 3
-            -4, // band 4
-            -7, // band 5
-            -6, // band 6
-             -1  // band 7
-        };
-
 const char *VfoStateStr[] = {
        [VFO_STATE_NORMAL]="",
        [VFO_STATE_BUSY]="BUSY",
@@ -80,17 +70,19 @@ const char *VfoStateStr[] = {
        [VFO_STATE_VOLTAGE_HIGH]="VOLT HIGH"
 };
 
-// ***************************************************************************
+// ----------------------------------------
 
-static void DrawSmallAntennaAndBars(uint8_t *p, unsigned int level)
+static void DrawSmallPowerBars(uint8_t *p, unsigned int level)
 {
     if(level>6)
         level = 6;
 
-    memcpy(p, BITMAP_Antenna, ARRAY_SIZE(BITMAP_Antenna));
+    char bar = 0b00111110;
 
-    for(uint8_t i = 1; i <= level; i++) {
-        char bar = (0xff << (6-i)) & 0x7F;
+    for(uint8_t i = 0; i <= level; i++) {
+        if(gSetting_set_gui) {
+            bar = (0xff << (6-i)) & 0x7F;
+        }
         memset(p + 2 + i*3, bar, 2);
     }
 }
@@ -166,15 +158,17 @@ static void DrawLevelBar(uint8_t xpos, uint8_t line, uint8_t level, uint8_t bars
 #endif
 
 #ifdef ENABLE_AUDIO_BAR
-
 // Approximation of a logarithmic scale using integer arithmetic
-uint8_t log2_approx(unsigned int value) {
+static uint8_t log2_approx(unsigned int value) {
     uint8_t log = 0;
     while (value >>= 1) {
         log++;
     }
     return log;
 }
+#endif
+
+#ifdef ENABLE_AUDIO_BAR
 
 void UI_DisplayAudioBar(void)
 {
@@ -239,6 +233,135 @@ void UI_DisplayAudioBar(void)
 }
 #endif
 
+#ifdef ENABLE_FEAT_F4HWN_AUDIO_SCOPE
+
+#define SCOPE_SAMPLES        43   // number of columns (43 × 3px = 128px wide)
+#define SCOPE_NOISE_GATE     50u  // minimum range below which the display shows baseline
+#define SCOPE_FLOOR_RISE     2u   // floor rise per frame (+100 units/s at 20ms/frame)
+#define SCOPE_FLOOR_DROP_SHR 3u   // floor drop IIR shift: drop by (floor-min) >> N per frame (~160ms to halve)
+#define SCOPE_VOLUME_MIN     200u // let's assume that the sound level in silence is 200
+
+void UI_DisplayAudioScope(void)
+{
+    static uint16_t g_scope_buf[SCOPE_SAMPLES];
+    static uint8_t  g_scope_write      = 0;
+    static uint16_t g_scope_floor      = SCOPE_VOLUME_MIN;     // persistent floor: snaps down fast, rises slowly
+    static uint8_t  g_scope_ready      = 0;                    // number of valid samples since TX entry
+
+    // REG_64 (VoiceAmplitudeOut) is only meaningful in TX (mic input).
+    // FM RX audio is frequency-encoded — no register gives the instantaneous waveform.
+
+// ------------------------------ Sample audio amplitude ------------------------------
+
+    static bool s_was_tx = false;
+
+    if (gCurrentFunction != FUNCTION_TRANSMIT) {
+        s_was_tx = false;
+        return;
+    }
+
+    // This prevents a sudden spike on the bar caused by release the PTT button
+    if (!GPIO_IsPttPressed()
+#ifdef ENABLE_VOX
+    && !gEeprom.VOX_SWITCH
+#endif
+#ifdef ENABLE_FEAT_F4HWN
+    && !gSetting_set_ptt_session
+#endif
+    )
+    return;
+
+    if (!s_was_tx) {
+        // TX entry: full reset so every new transmission starts from a clean state
+        for (uint8_t i = 0; i < SCOPE_SAMPLES; i++) g_scope_buf[i] = SCOPE_VOLUME_MIN;
+        g_scope_write      = 0u;
+        g_scope_floor      = SCOPE_VOLUME_MIN;
+        s_was_tx           = true;
+    }
+
+    // The first 7 bars after turning on the radio
+    // will not display any values: they cause high bars.
+    if (g_scope_ready >= 7)
+        g_scope_buf[g_scope_write] = BK4819_GetVoiceAmplitudeOut();
+    else
+        g_scope_ready++;
+        
+    // If the reading is 0, it is definitely an incorrect value
+    // caused by the microphone being muted - set it to 200.
+    if (g_scope_buf[g_scope_write] == 0) 
+        g_scope_buf[g_scope_write] =  SCOPE_VOLUME_MIN;
+
+    g_scope_write = (g_scope_write + 1u) % SCOPE_SAMPLES;
+
+// --------------------------------- Refresh display ---------------------------------
+
+    if (gLowBattery && !gLowBatteryConfirmed)
+        return;
+
+    if (gScreenToDisplay != DISPLAY_MAIN
+#ifdef ENABLE_DTMF_CALLING
+        || gDTMF_CallState != DTMF_CALL_STATE_NONE
+#endif
+        )
+        return;
+
+#if defined(ENABLE_ALARM) || defined(ENABLE_TX1750)
+    if (gAlarmState != ALARM_STATE_OFF)
+        return;
+#endif
+
+#ifdef ENABLE_FEAT_F4HWN
+    RxBlinkLed = 0;
+    RxBlinkLedCounter = 0;
+    BK4819_ToggleGpioOut(BK4819_GPIO6_PIN2_GREEN, false);
+    const unsigned int line = isMainOnly() ? 5 : 3;
+#else
+    const unsigned int line = 3;
+#endif
+
+    uint8_t *p_line = gFrameBuffer[line];
+    memset(p_line, 0, LCD_WIDTH);
+
+    // Find min and max across current buffer
+    uint16_t min_val = g_scope_buf[0];
+    uint16_t max_val = g_scope_buf[0];
+    for (uint8_t i = 1u; i < SCOPE_SAMPLES; i++) {
+        if (g_scope_buf[i] < min_val) min_val = g_scope_buf[i];
+        if (g_scope_buf[i] > max_val) max_val = g_scope_buf[i];
+    }
+
+    // Floor tracks buffer minimum with asymmetric IIR:
+    // - drops toward min smoothly (SCOPE_FLOOR_DROP_SHR), avoiding instant-snap ghost
+    // - rises slowly (SCOPE_FLOOR_RISE/frame) to handle loud constant voice
+    if (g_scope_floor > min_val)
+        g_scope_floor -= ((g_scope_floor - min_val) >> SCOPE_FLOOR_DROP_SHR) + 1u;
+    else
+        g_scope_floor += SCOPE_FLOOR_RISE;
+
+    const uint16_t range = (max_val > g_scope_floor) ? (max_val - g_scope_floor) : 0u;
+
+    for (uint8_t i = 0u; i < SCOPE_SAMPLES; i++) {
+        const uint8_t  idx    = (g_scope_write + i) % SCOPE_SAMPLES;
+        uint8_t        height = 0u;
+        if (range >= SCOPE_NOISE_GATE) {
+            const uint16_t v = (g_scope_buf[idx] > g_scope_floor) ? (g_scope_buf[idx] - g_scope_floor) : 0u;
+            height = (uint8_t)((uint32_t)v * 7u / range);
+        }
+        // Filled column using bits 6..0 only (bit 7 always off to avoid overlap with text below)
+        // At silence (height 0): single pixel at bit 6 (baseline)
+        const uint8_t mask = (height > 0u) ? (uint8_t)((0x7Fu << (7u - height)) & 0x7Fu) : 0x40u;
+        // 2px column + 1px gap per sample
+
+        uint8_t *p_col = &p_line[i * 3u];
+        p_col[0] = mask;
+        p_col[1] = mask;
+
+    }
+
+    ST7565_BlitLine(line);
+}
+#endif  // ENABLE_FEAT_F4HWN_AUDIO_SCOPE
+
 void DisplayRSSIBar(const bool now)
 {
 #if defined(ENABLE_RSSI_BAR)
@@ -273,24 +396,23 @@ void DisplayRSSIBar(const bool now)
     //sprintf(String, "%d", RxBlink);
     //UI_PrintStringSmallBold(String, 80, 0, RxLine);
 
-    /*
     if(RxLine >= 0 && center_line != CENTER_LINE_IN_USE)
     {
-        if (RxBlink == 0 || RxBlink == 1) {
-            UI_PrintStringSmallBold("RX", 8, 0, RxLine);
-            //GUI_DisplaySmallest("RX", 10, (RxLine * 8) + 1, false, true);
+        static bool clean = false;
+        uint8_t *p_line0 = gFrameBuffer[RxLine + 0];
 
-            if (RxBlink == 1) RxBlink = 2;
+        clean = !clean;
+
+        if(clean) {
+            for(uint8_t i = 0; i < sizeof(BITMAP_VFO_Default); i++)
+                p_line0[i] = (p_line0[i] & 0x80) | BITMAP_VFO_Default[i];
         } else {
-            for (uint8_t i = 8; i < 24; i++)
-            {
-                gFrameBuffer[RxLine][i] = 0x00;
-            }
-            RxBlink = 1;
+            for(uint8_t i = 0; i < sizeof(BITMAP_VFO_Empty); i++)
+                p_line0[i] = (p_line0[i] & 0x80) | BITMAP_VFO_Empty[i];
         }
+
         ST7565_BlitLine(RxLine);
     }
-    */
 #else
     const unsigned int line = 3;
 #endif
@@ -331,22 +453,34 @@ void DisplayRSSIBar(const bool now)
 #endif
         + dBmCorrTable[gRxVfo->Band];
 
-    rssi_dBm = -rssi_dBm;
-
-    if(rssi_dBm > 141) rssi_dBm = 141;
-    if(rssi_dBm < 53) rssi_dBm = 53;
-
-    uint8_t s_level = 0;
-    uint8_t overS9dBm = 0;
+    // IARU VHF/UHF S-meter: S9 = -93 dBm, 1 S-unit = 6 dB
+    // S(n) threshold = -93 + (n - 9) * 6
+    uint8_t s_level    = 0;
+    uint8_t overS9dBm  = 0;
     uint8_t overS9Bars = 0;
 
-    if(rssi_dBm >= 93) {
-        s_level = map(rssi_dBm, 141, 93, 1, 9);
-    }
-    else {
+    // if      (rssi_dBm >= -93)  s_level = 9;  // S9  = -93 dBm
+    // else if (rssi_dBm >= -99)  s_level = 8;  // S8  = -99 dBm
+    // else if (rssi_dBm >= -105) s_level = 7;  // S7  = -105 dBm
+    // else if (rssi_dBm >= -111) s_level = 6;  // S6  = -111 dBm
+    // else if (rssi_dBm >= -117) s_level = 5;  // S5  = -117 dBm
+    // else if (rssi_dBm >= -123) s_level = 4;  // S4  = -123 dBm
+    // else if (rssi_dBm >= -129) s_level = 3;  // S3  = -129 dBm
+    // else if (rssi_dBm >= -135) s_level = 2;  // S2  = -135 dBm
+    // else if (rssi_dBm >= -141) s_level = 1;  // S1  = -141 dBm
+    // else                       s_level = 0;  // S0 (below -141 dBm)
+
+    if (rssi_dBm >= -93)
         s_level = 9;
-        overS9dBm = map(rssi_dBm, 93, 53, 0, 40);
-        overS9Bars = map(overS9dBm, 0, 40, 0, 4);
+    else if (rssi_dBm < -141)
+        s_level = 0;
+    else 
+        s_level = (rssi_dBm + 147) / 6;
+
+    if (s_level == 9) {
+        // Compute over-S9 dB directly
+        overS9dBm  = (uint8_t)MIN(rssi_dBm - (-93), 40);
+        overS9Bars = overS9dBm / 10;
     }
 #else
     const int16_t s0_dBm   = -gEeprom.S0_LEVEL;                  // S0 .. base level
@@ -366,12 +500,12 @@ void DisplayRSSIBar(const bool now)
 #ifdef ENABLE_FEAT_F4HWN
     if (gSetting_set_gui)
     {
-        sprintf(str, "%3d", -rssi_dBm);
+        sprintf(str, "%3d", rssi_dBm);
         UI_PrintStringSmallNormal(str, LCD_WIDTH + 8, 0, line - 1);
     }
     else
     {
-        sprintf(str, "% 4d %s", -rssi_dBm, "dBm");
+        sprintf(str, "% 4d %s", rssi_dBm, "dBm");
         if(isMainOnly())
             GUI_DisplaySmallest(str, 2, 41, false, true);
         else
@@ -419,7 +553,7 @@ void DisplayRSSIBar(const bool now)
     uint8_t *pLine = (gEeprom.RX_VFO == 0)? gFrameBuffer[2] : gFrameBuffer[6];
     if (now)
         memset(pLine, 0, 23);
-    DrawSmallAntennaAndBars(pLine, Level);
+    DrawSmallPowerBars(pLine, Level);
     if (now)
         ST7565_BlitFullScreen();
 #endif
@@ -528,7 +662,7 @@ void UI_MAIN_TimeSlice500ms(void)
     }
 }
 
-// ***************************************************************************
+// ----------------------------------------
 
 void UI_DisplayMain(void)
 {
@@ -554,32 +688,7 @@ void UI_DisplayMain(void)
         return;
     }
 #else
-    if (gEeprom.KEY_LOCK && gKeypadLocked > 0)
-    {   // tell user how to unlock the keyboard
-        uint8_t shift = 3;
-
-        /*
-        BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1_RED, true);
-        SYSTEM_DelayMs(50);
-        BK4819_ToggleGpioOut(BK4819_GPIO5_PIN1_RED, false);
-        SYSTEM_DelayMs(50);
-        */
-
-        if(isMainOnly())
-        {
-            shift = 5;
-        }
-        //memcpy(gFrameBuffer[shift] + 2, gFontKeyLock, sizeof(gFontKeyLock));
-        UI_PrintStringSmallBold("UNLOCK KEYBOARD", 12, 0, shift);
-        //memcpy(gFrameBuffer[shift] + 120, gFontKeyLock, sizeof(gFontKeyLock));
-
-        /*
-        for (uint8_t i = 12; i < 116; i++)
-        {
-            gFrameBuffer[shift][i] ^= 0xFF;
-        }
-        */
-    }
+    UI_DisplayUnlockKeyboard(isMainOnly() ? 5 : 3);
 #endif
 
     unsigned int activeTxVFO = gRxVfoIsActive ? gEeprom.RX_VFO : gEeprom.TX_VFO;
@@ -771,46 +880,51 @@ void UI_DisplayMain(void)
         {   // receiving .. show the RX symbol
             mode = VFO_MODE_RX;
             //if (FUNCTION_IsRx() && gEeprom.RX_VFO == vfo_num) {
-            if (FUNCTION_IsRx() && gEeprom.RX_VFO == vfo_num && VfoState[vfo_num] == VFO_STATE_NORMAL) {
+            if (FUNCTION_IsRx()) {
+                if (gEeprom.RX_VFO == vfo_num && VfoState[vfo_num] == VFO_STATE_NORMAL) {
 #ifdef ENABLE_FEAT_F4HWN
-                RxBlinkLed = 1;
-                RxBlinkLedCounter = 0;
-                RxLine = line;
-                RxOnVfofrequency = frequency;
-                if(!isMainVFO)
-                {
-                    RxBlink = 1;
-                }
-                else
-                {
-                    RxBlink = 0;
-                }
+                    RxBlinkLed = 1;
+                    RxBlinkLedCounter = 0;
+                    RxLine = line;
+                    RxOnVfofrequency = frequency;
+                    // if(!isMainVFO)
+                    // {
+                    //     RxBlink = 1;
+                    // }
+                    // else
+                    // {
+                    //     RxBlink = 0;
+                    // }
 
-                if (RxBlink == 0 || RxBlink == 1) {
-                    if(gRxVfo->Modulation == MODULATION_AM)
-                        GUI_DisplaySmallest("AIR", 10, RxLine == 0 ? 1 : 33, false, true);
-                    else {
-                        #ifdef ENABLE_FEAT_F4HWN_AUDIO
-                            strcpy(String, gSubMenu_SET_AUD[gSetting_set_audio]);
-                        #else
-                            strcpy(String, "RX");
-                        #endif
-                        GUI_DisplaySmallest(String, 10, RxLine == 0 ? 1 : 33, false, true);
-                    }
+                    // if (RxBlink == 0 || RxBlink == 1) {
+                        if(gRxVfo->Modulation == MODULATION_AM)
+                            GUI_DisplaySmallest("AIR", 10, RxLine == 0 ? 1 : 33, false, true);
+                        else {
+                            #ifdef ENABLE_FEAT_F4HWN_AUDIO
+                                strcpy(String, gSubMenu_SET_AUD[gSetting_set_audio]);
+                            #else
+                                strcpy(String, "RX");
+                            #endif
+                            GUI_DisplaySmallest(String, 10, RxLine == 0 ? 1 : 33, false, true);
+                        }
 
-                    //UI_PrintStringSmallBold("RX", 8, 0, RxLine);
-                }
+                        //UI_PrintStringSmallBold("RX", 8, 0, RxLine);
+                    // }
 #else
-                UI_PrintStringSmallBold("RX", 8, 0, line);
+                    UI_PrintStringSmallBold("RX", 8, 0, line);
 #endif
-            }
+                }
 #ifdef ENABLE_FEAT_F4HWN
-            else
-            {
-                if(RxOnVfofrequency == frequency && !isMainOnly())
-                {
-                    UI_PrintStringSmallNormal(">>", 8, 0, line);
+                else {
+                    if(RxBlinkLed == 1)
+                        RxBlinkLed = 2;
+                }
+            }
+            else {
+                if(RxOnVfofrequency == frequency && !isMainOnly()) {
+                    //UI_PrintStringSmallNormal(">>", 8, 0, line);
                     //memcpy(p_line0 + 14, BITMAP_VFO_Default, sizeof(BITMAP_VFO_Default));
+                    GUI_DisplaySmallest(">>", 8, RxLine == 0 ? 1 : 33, false, true);
                 }
 
                 if(RxBlinkLed == 1)
@@ -821,21 +935,60 @@ void UI_DisplayMain(void)
 
         if (IS_MR_CHANNEL(gEeprom.ScreenChannel[vfo_num]))
         {   // channel mode
-            const unsigned int x = 3;
+            const unsigned int x = 1;
             const bool inputting = gInputBoxIndex != 0 && gEeprom.TX_VFO == vfo_num;
             if (!inputting || gScanStateDir != SCAN_OFF)
                 sprintf(String, "%04u", gEeprom.ScreenChannel[vfo_num] + 1);
             else
                 sprintf(String, "%.4s", INPUTBOX_GetAscii());  // show the input text
-            UI_PrintStringSmallNormalInverse(String, x, 0, line + 1);
+
+            //if (gSetting_set_gui) {
+                UI_PrintStringSmallNormalInverse(String, x, 0, line + 1);
+            /*
+            }
+            else
+            {
+                GUI_DisplaySmallest(String, x + 1, line == 0 ? 9 : 41, false, true);
+                gFrameBuffer[line + 1][0] ^= 0x1C;
+                gFrameBuffer[line + 1][1] ^= 0x3E;
+                for (uint8_t i = 2; i < 21; i++) {
+                    gFrameBuffer[line + 1][i] ^= 0x7F;
+                }
+                gFrameBuffer[line + 1][21] ^= 0x3E;
+                gFrameBuffer[line + 1][22] ^= 0x1C;
+
+            }
+            */
         }
         else if (IS_FREQ_CHANNEL(gEeprom.ScreenChannel[vfo_num]))
         {   // frequency mode
             // show the frequency band number
             const unsigned int x = 2;
-            char * buf = gEeprom.VfoInfo[vfo_num].pRX->Frequency < _1GHz_in_KHz ? "" : "+";
-            sprintf(String, "F%u%s", 1 + gEeprom.ScreenChannel[vfo_num] - FREQ_CHANNEL_FIRST, buf);
-            UI_PrintStringSmallNormal(String, x, 0, line + 1);
+            const uint8_t f = 1 + gEeprom.ScreenChannel[vfo_num] - FREQ_CHANNEL_FIRST;
+            const bool over1GHz = gEeprom.VfoInfo[vfo_num].pRX->Frequency >= _1GHz_in_KHz;
+
+            sprintf(String, over1GHz ? "F%u+" : "F%u", f);
+            //if (gSetting_set_gui) {
+                UI_PrintStringSmallNormalInverse(String, x, 0, line + 1);
+            /*
+            }
+            else
+            {
+                GUI_DisplaySmallest(String, x + 2, line == 0 ? 9 : 41, false, true);
+                uint8_t g = 13;
+                if(over1GHz)
+                    g = 17;
+
+                gFrameBuffer[line + 1][0] ^= 0x1C;
+                gFrameBuffer[line + 1][1] ^= 0x3E;
+                for (uint8_t i = 2; i < g; i++) {
+                    gFrameBuffer[line + 1][i] ^= 0x7F;
+                }
+                gFrameBuffer[line + 1][g] ^= 0x3E;
+                gFrameBuffer[line + 1][g + 1] ^= 0x1C;
+
+            }
+            */
         }
 #ifdef ENABLE_NOAA
         else
@@ -852,7 +1005,7 @@ void UI_DisplayMain(void)
         }
 #endif
 
-        // ************
+        // ----------------------------------------
 
         enum VfoState_t state = VfoState[vfo_num];
 
@@ -917,20 +1070,44 @@ void UI_DisplayMain(void)
                         countList = 0;
                     }
 
-                    const char *displayStr = (countList == MR_CHANNELS_LIST + 1) ? "ALL" : 
-                                             (countList == 0) ? "OFF" : String;
-                    uint8_t xStart = (countList > 0 && countList != MR_CHANNELS_LIST + 1) ? 117 : 113;
-                    uint8_t xDisplay = (countList > 0 && countList != MR_CHANNELS_LIST + 1) ? 119 : 115;
+                    const char *displayStr;
+                    uint8_t xStart, xDisplay;
 
-                    if(countList > 0 && countList != MR_CHANNELS_LIST + 1) {
-                        sprintf(String, "%02d", countList);
+                    if (countList == MR_CHANNELS_LIST + 1) {
+                        displayStr = "ALL";
+                        xStart = 113;
+                        xDisplay = 115;
+                    } 
+                    else if (countList == 0) {
+                        displayStr = "OFF";
+                        xStart = 113;
+                        xDisplay = 115;
+                    } 
+                    else {
+                        // List 1 to MR_CHANNELS_LIST
+                        const char *name = gListName[countList - 1];
+                        
+                        // If name is empty/invalid, display number
+                        if (IsEmptyName(name, sizeof(gListName[0]))) {
+                            sprintf(String, "%02d", countList);
+                            xStart = 117;  // 2-digit number aligned right
+                            xDisplay = 119;
+                        } 
+                        else {
+                            sprintf(String, "%.3s", name);
+                            xStart = 113;  // 3-char name aligned left
+                            xDisplay = 115;
+                        }
+                        displayStr = String;
                     }
 
-                    GUI_DisplaySmallest(displayStr, xDisplay, line == 0 ? 2 : 34, false, true);
+                    GUI_DisplaySmallest(displayStr, xDisplay, line == 0 ? 1 : 33, false, true);
 
-                    for (uint8_t x = xStart; x < 128; x++) {
-                        gFrameBuffer[line][x] ^= 0xFE;
+                    gFrameBuffer[line][xStart] ^= 0x3E;
+                    for (uint8_t x = xStart + 1; x < 127; x++) {
+                        gFrameBuffer[line][x] ^= 0x7F;
                     }
+                    gFrameBuffer[line][127] ^= 0x3E;
 
                 }
                 else
@@ -940,11 +1117,13 @@ void UI_DisplayMain(void)
                     uint8_t xStart = 117;
                     uint8_t xDisplay = 119;
                     
-                    GUI_DisplaySmallest(displayStr, xDisplay, line == 0 ? 2 : 34, false, true);
+                    GUI_DisplaySmallest(displayStr, xDisplay, line == 0 ? 1 : 33, false, true);
 
-                    for (uint8_t x = xStart; x < 128; x++) {
-                        gFrameBuffer[line][x] ^= 0xFE;
+                    gFrameBuffer[line][xStart] ^= 0x3E;
+                    for (uint8_t x = xStart + 1; x < 127; x++) {
+                        gFrameBuffer[line][x] ^= 0x7F;
                     }
+                    gFrameBuffer[line][127] ^= 0x3E;
                 }
 
                 #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
@@ -983,7 +1162,7 @@ void UI_DisplayMain(void)
                         break;
 
                     case MDF_CHANNEL:   // show the channel number
-                        sprintf(String, "CH-%03u", gEeprom.ScreenChannel[vfo_num] + 1);
+                        sprintf(String, "CH-%04u", gEeprom.ScreenChannel[vfo_num] + 1);
                         UI_PrintString(String, 36, 0, line, 8);
                         break;
 
@@ -993,19 +1172,19 @@ void UI_DisplayMain(void)
                         SETTINGS_FetchChannelName(String, gEeprom.ScreenChannel[vfo_num]);
                         if (String[0] == 0)
                         {   // no channel name, show the channel number instead
-                            sprintf(String, "CH-%03u", gEeprom.ScreenChannel[vfo_num] + 1);
+                            sprintf(String, "CH-%04u", gEeprom.ScreenChannel[vfo_num] + 1);
                         }
 
                         if (gEeprom.CHANNEL_DISPLAY_MODE == MDF_NAME) {
-                            String[9] = 0;
-                            UI_PrintString(String, 36, 0, line, 8);
+                            String[10] = 0;
+                            UI_PrintString(String, 33, 0, line, 8);
                         }
                         else {
 #ifdef ENABLE_FEAT_F4HWN
                             if (isMainOnly())
                             {
-                                String[9] = 0;
-                                UI_PrintString(String, 36, 0, line, 8);
+                                String[10] = 0;
+                                UI_PrintString(String, 33, 0, line, 8);
                             }
                             else
                             {
@@ -1082,7 +1261,7 @@ void UI_DisplayMain(void)
             }
         }
 
-        // ************
+        // ----------------------------------------
 
         {   // show the TX/RX level
             int8_t Level = -1;
@@ -1109,9 +1288,15 @@ void UI_DisplayMain(void)
                     Level = 2;
                 }
                 */
-                Level = gRxVfo->OUTPUT_POWER - 1;
+
+                uint8_t currentPower = gRxVfo->OUTPUT_POWER;
+
+                if(currentPower == OUTPUT_POWER_USER)
+                    Level = gSetting_set_pwr;
+                else
+                    Level = currentPower - 1;
             }
-            else
+            else 
             if (mode == VFO_MODE_RX)
             {   // RX signal level
                 #ifndef ENABLE_RSSI_BAR
@@ -1121,10 +1306,10 @@ void UI_DisplayMain(void)
                 #endif
             }
             if(Level >= 0)
-                DrawSmallAntennaAndBars(p_line1 + LCD_WIDTH, Level);
+                DrawSmallPowerBars(p_line1 + LCD_WIDTH, Level);
         }
 
-        // ************
+        // ----------------------------------------
 
         String[0] = '\0';
         const VFO_Info_t *vfoInfo = &gEeprom.VfoInfo[vfo_num];
@@ -1420,6 +1605,14 @@ void UI_DisplayMain(void)
 
         const bool rx = FUNCTION_IsRx();
 
+#ifdef ENABLE_FEAT_F4HWN_AUDIO_SCOPE
+        if (gSetting_mic_bar && gCurrentFunction == FUNCTION_TRANSMIT) {
+            // Reserve the line so no other element overwrites it.
+            // Actual drawing is handled exclusively by the app.c timeslice.
+            center_line = CENTER_LINE_AUDIO_SCOPE;
+        }
+        else
+#endif
 #ifdef ENABLE_AUDIO_BAR
         if (gSetting_mic_bar && gCurrentFunction == FUNCTION_TRANSMIT) {
             center_line = CENTER_LINE_AUDIO_BAR;
@@ -1455,7 +1648,7 @@ void UI_DisplayMain(void)
         if (rx || gCurrentFunction == FUNCTION_FOREGROUND || gCurrentFunction == FUNCTION_POWER_SAVE)
         {
             #if 1
-                if (gSetting_live_DTMF_decoder && gDTMF_RX_live[0] != 0)
+                if (gSetting_live_DTMF_decoder && gDTMF_RX_live[0] != 0 && gKeypadLocked == 0)
                 {   // show live DTMF decode
                     const unsigned int len = strlen(gDTMF_RX_live);
                     const unsigned int idx = (len > (17 - 5)) ? len - (17 - 5) : 0;  // limit to last 'n' chars
@@ -1530,11 +1723,21 @@ void UI_DisplayMain(void)
     if (isMainOnly() && !gDTMF_InputMode)
     {
         sprintf(String, "VFO %s", activeTxVFO ? "B" : "A");
+        GUI_DisplaySmallest(String, 107, 50, false, true);
+
+        gFrameBuffer[6][105] ^= 0x7C;
+        for (uint8_t x = 106; x < 127; x++) {
+            gFrameBuffer[6][x] ^= 0xFE;
+        }
+        gFrameBuffer[6][127] ^= 0x7C;
+
+        /*
         UI_PrintStringSmallBold(String, 92, 0, 6);
         for (uint8_t i = 92; i < 128; i++)
         {
             gFrameBuffer[6][i] ^= 0x7F;
         }
+        */
     }
     //#ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
     //}
@@ -1543,5 +1746,3 @@ void UI_DisplayMain(void)
 
     ST7565_BlitFullScreen();
 }
-
-// ***************************************************************************

App/ui/main.h

@@ -17,10 +17,13 @@
 #ifndef UI_MAIN_H
 #define UI_MAIN_H
 
+#include <stdint.h>
+
 enum center_line_t {
     CENTER_LINE_NONE = 0,
     CENTER_LINE_IN_USE,
     CENTER_LINE_AUDIO_BAR,
+    CENTER_LINE_AUDIO_SCOPE,
     CENTER_LINE_RSSI,
     CENTER_LINE_AM_FIX_DATA,
     CENTER_LINE_DTMF_DEC,
@@ -36,9 +39,13 @@ enum Vfo_txtr_mode{
 typedef enum center_line_t center_line_t;
 
 extern center_line_t center_line;
-extern const int8_t dBmCorrTable[7];
 
+#ifdef ENABLE_AUDIO_BAR
 void UI_DisplayAudioBar(void);
+#endif
+#ifdef ENABLE_FEAT_F4HWN_AUDIO_SCOPE
+void UI_DisplayAudioScope(void);
+#endif
 void UI_MAIN_TimeSlice500ms(void);
 void UI_DisplayMain(void);
 

App/ui/menu.c

@@ -646,7 +646,11 @@ void UI_DisplayMenu(void)
         case MENU_MIC:
             {   // display the mic gain in actual dB rather than just an index number
                 const uint8_t mic = gMicGain_dB2[gSubMenuSelection];
-                sprintf(String, "+%u.%01udB", mic / 2, mic % 2);
+                sprintf(String, "+%u.%udB", mic / 2, (mic % 2) * 5);
+
+                gaugeLine = 4;
+                gaugeMin = 0;
+                gaugeMax = 8;
             }
             break;
 
@@ -703,15 +707,14 @@ void UI_DisplayMenu(void)
             if (!gIsInSubMenu || gInputBoxIndex == 0)
             {
                 sprintf(String, "%3d.%05u", gSubMenuSelection / 100000, abs(gSubMenuSelection) % 100000);
-                UI_PrintString(String, menu_item_x1, menu_item_x2, 1, 8);
             }
             else
             {
                 const char * ascii = INPUTBOX_GetAscii();
                 sprintf(String, "%.3s.%.3s  ",ascii, ascii + 3);
-                UI_PrintString(String, menu_item_x1, menu_item_x2, 1, 8);
             }
 
+            UI_PrintString(String, menu_item_x1, menu_item_x2, 1, 8);
             UI_PrintString("MHz",  menu_item_x1, menu_item_x2, 3, 8);
 
             already_printed = true;
@@ -969,15 +972,28 @@ void UI_DisplayMenu(void)
                 strcpy(String, "ALL");
             else if (gSubMenuSelection == 0)
                 strcpy(String, "OFF");
-            else
-                sprintf(String, "%u", gSubMenuSelection);
+            else {
+                const char *name = gListName[gSubMenuSelection - 1];
+                
+                // If first character is empty/invalid, display "N/A"
+                if (IsEmptyName(name, sizeof(gListName[0])))
+                    sprintf(String, "%02u", gSubMenuSelection);
+                else
+                    sprintf(String, "%02u (%.3s)", gSubMenuSelection, name);
+            }
             break;
 
         case MENU_S_LIST:
             if (gSubMenuSelection == MR_CHANNELS_LIST + 1)
                 strcpy(String, "ALL");
-            else
-                sprintf(String, "%u", gSubMenuSelection);
+            else {
+                const char *name = gListName[gSubMenuSelection - 1];
+                // If first character is empty/invalid, display "N/A"
+                if (IsEmptyName(name, sizeof(gListName[0])))
+                    sprintf(String, "%02u", gSubMenuSelection);
+                else
+                    sprintf(String, "%02u (%.3s)", gSubMenuSelection, name);
+            }
             break;
 
         #ifdef ENABLE_ALARM
@@ -1204,7 +1220,7 @@ void UI_DisplayMenu(void)
                     gaugeMax = 63;
                     //#endif
                 }
-                gEeprom.VOLUME_GAIN = gSubMenuSelection;
+                // gEeprom.VOLUME_GAIN = gSubMenuSelection;
                 BK4819_WriteRegister(BK4819_REG_48,
                     (11u << 12)                |     // ??? .. 0 ~ 15, doesn't seem to make any difference
                     ( 0u << 10)                |     // AF Rx Gain-1

App/ui/status.c

@@ -101,31 +101,37 @@ void UI_DisplayStatus()
                 {
                     if(gEeprom.SCAN_LIST_ENABLED==1) {
                         sprintf(str, "%s+", "ALL");
-                        end = 19;
+                        end = 18;
                     }
                     else
                     {
                         sprintf(str, "%s", "ALL");
-                        end = 15;
+                        end = 14;
                     }
                 }
                 else
                 {
-                    if(gEeprom.SCAN_LIST_ENABLED==1) {
-                        sprintf(str, "%02d+", gEeprom.SCAN_LIST_DEFAULT);
-                        end = 15;
-                    }
+                    const char *name = gListName[gEeprom.SCAN_LIST_DEFAULT - 1];
+
+                    // Check if name is valid
+                    if (!IsEmptyName(name, sizeof(gListName[0]))) {
+                        sprintf(str, "%.3s%s", name, gEeprom.SCAN_LIST_ENABLED ? "+" : "");
+                        end = gEeprom.SCAN_LIST_ENABLED ? 18 : 14;
+                    } 
                     else {
-                        sprintf(str, "%02d", gEeprom.SCAN_LIST_DEFAULT);
-                        end = 11;
+                        sprintf(str, "%02d%s", gEeprom.SCAN_LIST_DEFAULT, gEeprom.SCAN_LIST_ENABLED ? "+" : "");
+                        end = gEeprom.SCAN_LIST_ENABLED ? 14 : 10;
                     }
                 }
 
                 GUI_DisplaySmallest(str, 2, 1, true, true);
-                for (uint8_t x = 0; x < end; x++)
+
+                gStatusLine[0] ^= 0x3E;
+                for (uint8_t x = 1; x < end; x++)
                 {
                     gStatusLine[x] ^= 0x7F;
                 }
+                gStatusLine[end] ^= 0x3E;
             }
             else {  // frequency mode
                 memcpy(line + x + 1, gFontS, sizeof(gFontS));
@@ -167,31 +173,32 @@ void UI_DisplayStatus()
             else
         #endif
             {
-                #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
-                if(gEeprom.MENU_LOCK == true) {
-                    memcpy(line + x + 2, gFontRO, sizeof(gFontRO));
-                }
-                else
-                {
-                #endif
-                    uint8_t dw = (gEeprom.DUAL_WATCH != DUAL_WATCH_OFF) + (gEeprom.CROSS_BAND_RX_TX != CROSS_BAND_OFF) * 2;
-                    if(dw == 1 || dw == 3) { // DWR - dual watch + respond
-                        if(gDualWatchActive)
-                            memcpy(line + x + (dw==1?0:2), gFontDWR, sizeof(gFontDWR) - (dw==1?0:5));
-                        else
-                            memcpy(line + x + 3, gFontHold, sizeof(gFontHold));
-                    }
-                    else if(dw == 2) { // XB - crossband
-                        memcpy(line + x + 2, gFontXB, sizeof(gFontXB));
+                if(!gAirCopyBootMode) {
+                    #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
+                    if(gEeprom.MENU_LOCK == true) {
+                        memcpy(line + x + 2, gFontRO, sizeof(gFontRO));
                     }
                     else
                     {
-                        if(!gAirCopyBootMode)
+                    #endif
+                        uint8_t dw = (gEeprom.DUAL_WATCH != DUAL_WATCH_OFF) + (gEeprom.CROSS_BAND_RX_TX != CROSS_BAND_OFF) * 2;
+                        if(dw == 1 || dw == 3) { // DWR - dual watch + respond
+                            if(gDualWatchActive)
+                                memcpy(line + x + (dw==1?0:2), gFontDWR, sizeof(gFontDWR) - (dw==1?0:5));
+                            else
+                                memcpy(line + x + 3, gFontHold, sizeof(gFontHold));
+                        }
+                        else if(dw == 2) { // XB - crossband
+                            memcpy(line + x + 2, gFontXB, sizeof(gFontXB));
+                        }
+                        else
+                        {
                             memcpy(line + x + 2, gFontMO, sizeof(gFontMO));
+                        }
+                    #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
                     }
-                #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
+                    #endif
                 }
-                #endif
             }
         }
         x += sizeof(gFontDWR) + 3;
@@ -233,15 +240,8 @@ void UI_DisplayStatus()
         size = sizeof(gFontKeyLock);
     }
     else if (gWasFKeyPressed) {
-        #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
-        if (!gEeprom.MENU_LOCK) {
-            src = gFontF;
-            size = sizeof(gFontF);
-        }
-        #else
         src = gFontF;
         size = sizeof(gFontF);
-        #endif
     }
     #ifdef ENABLE_FEAT_F4HWN
         else if (gMute) {

App/ui/ui.c

@@ -94,9 +94,8 @@ void GUI_SelectNextDisplay(GUI_DisplayType_t Display)
         gAskForConfirmation  = 0;
         gAskToSave           = false;
         gAskToDelete         = false;
-        gWasFKeyPressed      = false;
 
-        gUpdateStatus        = true;
+        HideFKeyIcon();
     }
 
     gScreenToDisplay = Display;

App/ui/welcome.c

@@ -15,6 +15,7 @@
  */
 
 #include <string.h>
+#include <stdint.h>
 
 #include "driver/py25q16.h"
 #include "driver/st7565.h"
@@ -32,6 +33,63 @@
     #include "screenshot.h"
 #endif
 
+#ifdef ENABLE_FEAT_F4HWN_MEM
+// Linker symbols (provided by the linker script)
+extern uint8_t _sdata;          // Start of .data in RAM
+extern uint8_t _edata;          // End of .data in RAM
+extern uint8_t _sbss;           // Start of .bss in RAM
+extern uint8_t _ebss;           // End of .bss in RAM
+
+// _eflash_used must be defined in the linker script immediately after the last
+// section with a FLASH load address (after .noncacheable). Example:
+//
+//   .noncacheable : {
+//       ...
+//   } > RAM AT> FLASH
+//   _eflash_used = LOADADDR(.noncacheable) + SIZEOF(.noncacheable);
+//
+// This gives the exact byte count that the linker reports as FLASH used.
+extern uint8_t _eflash_used;
+
+// Absolute symbols: their *address* IS the numeric size value (ARM/CMSIS convention).
+// RAM = .data + gap + .bss + heap_reserve + stack_reserve
+extern uint8_t _Min_Heap_Size;
+extern uint8_t _Min_Stack_Size;
+
+// Region sizes (must match your linker MEMORY regions)
+#define RAM_SIZE_BYTES     (16u * 1024u)
+#define FLASH_SIZE_BYTES   (118u * 1024u)
+
+// Base address of FLASH — must match ORIGIN(FLASH) in your linker script
+#define FLASH_BASE         (0x08002800u)
+
+static inline uint32_t span(const void* a, const void* b)
+{
+    return (uint32_t)((uintptr_t)b - (uintptr_t)a);
+}
+
+static void build_usage(uint32_t* ram_used, uint32_t* flash_used)
+{
+    // RAM: span from start of .data to end of .bss covers .data + alignment gap + .bss.
+    // Then add heap and stack reservations (absolute linker symbols: address = size).
+    // Proof: (0x20002A60 - 0x20000000) + 0x200 + 0x400 = 10848 + 512 + 1024 = 12384 B ✓
+    const uint32_t heap_size  = (uint32_t)(uintptr_t)&_Min_Heap_Size;
+    const uint32_t stack_size = (uint32_t)(uintptr_t)&_Min_Stack_Size;
+    *ram_used = span(&_sdata, &_ebss) + heap_size + stack_size;
+
+    // FLASH: _eflash_used is placed by the linker script right after the last
+    // section copied to FLASH (.data LMA + .noncacheable LMA).
+    // Note: _etext is NOT usable here because this linker script places .rodata
+    // sections AFTER _etext, making it an unreliable end-of-flash marker.
+    *flash_used = span((void*)FLASH_BASE, &_eflash_used);
+}
+
+static inline uint16_t pct_x100(uint32_t used, uint32_t total)
+{
+    return (uint16_t)((used * 10000u) / total); // 7559 => 75.59%
+}
+#endif
+
 void UI_DisplayReleaseKeys(void)
 {
     memset(gStatusLine,  0, sizeof(gStatusLine));
@@ -52,7 +110,7 @@ void UI_DisplayWelcome(void)
     char WelcomeString0[16];
     char WelcomeString1[16];
     char WelcomeString2[16];
-    char WelcomeString3[20];
+    char WelcomeString3[32];
 
     memset(gStatusLine,  0, sizeof(gStatusLine));
 
@@ -125,79 +183,37 @@ void UI_DisplayWelcome(void)
 #ifdef ENABLE_FEAT_F4HWN
         UI_PrintStringSmallNormal(Version, 0, 128, 4);
 
-        UI_DrawLineBuffer(gFrameBuffer, 0, 31, 127, 31, 1); // Be ware, status zone = 8 lines, the rest = 56 ->total 64
-
-        for (uint8_t i = 18; i < 110; i++)
+        UI_DrawLineBuffer(gFrameBuffer, 0, 35, 18, 35, 1);
+        gFrameBuffer[4][19] ^= 0x7F;
+        for (uint8_t x = 20; x < 108; x++)
         {
-            gFrameBuffer[4][i] ^= 0xFF;
+            gFrameBuffer[4][x] ^= 0xFF;
+            gFrameBuffer[3][x] ^= 0x80;
         }
+        gFrameBuffer[4][108] ^= 0x7F;
+        UI_DrawLineBuffer(gFrameBuffer, 109, 35, 127, 35, 1);
+
+        #ifdef ENABLE_FEAT_F4HWN_MEM
+            uint32_t ram_used   = 0;
+            uint32_t flash_used = 0;
+            build_usage(&ram_used, &flash_used);
+
+            const uint16_t ram_pct   = pct_x100(ram_used,   RAM_SIZE_BYTES);
+            const uint16_t flash_pct = pct_x100(flash_used, FLASH_SIZE_BYTES);
+
+            // No floats: 7559 => 75.59%
+            sprintf(WelcomeString3,
+            "FLASH %u.%02u %% - SRAM  %u.%02u %%",
+            (unsigned)(flash_pct / 100), (unsigned)(flash_pct % 100),
+            (unsigned)(ram_pct / 100),   (unsigned)(ram_pct % 100));
+
+            GUI_DisplaySmallest(WelcomeString3, 5, 1, true, true);
+            ST7565_BlitStatusLine();
+        #endif
 
         sprintf(WelcomeString3, "%s Edition", Edition);
         UI_PrintStringSmallNormal(WelcomeString3, 0, 127, 6);
 
-        /*
-        #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
-            #if ENABLE_FEAT_F4HWN_RESCUE_OPS > 1
-                UI_PrintStringSmallNormal(Edition, 18, 0, 6);
-                if(gEeprom.MENU_LOCK == true) {
-                    memcpy(gFrameBuffer[6] + 103, BITMAP_Ready, sizeof(BITMAP_Ready));
-                }
-                else
-                {
-                    memcpy(gFrameBuffer[6] + 103, BITMAP_NotReady, sizeof(BITMAP_NotReady));                    
-                }
-            #else
-                UI_PrintStringSmallNormal(Edition, 18, 0, 5);
-                memcpy(gFrameBuffer[5] + 103, BITMAP_Ready, sizeof(BITMAP_Ready));
-                
-                #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
-                    UI_PrintStringSmallNormal("RescueOps", 18, 0, 6);
-                    if(gEeprom.MENU_LOCK == true) {
-                        memcpy(gFrameBuffer[6] + 103, BITMAP_Ready, sizeof(BITMAP_Ready));
-                    }
-                    else
-                    {
-                        memcpy(gFrameBuffer[6] + 103, BITMAP_NotReady, sizeof(BITMAP_NotReady));
-                    }
-                #endif
-            #endif
-        #else
-            UI_PrintStringSmallNormal(Edition, 18, 0, 6);
-            memcpy(gFrameBuffer[6] + 103, BITMAP_Ready, sizeof(BITMAP_Ready));                    
-        #endif
-        */
-
-        /*
-        #ifdef ENABLE_SPECTRUM
-            #ifdef ENABLE_FMRADIO
-                    UI_PrintStringSmallNormal(Based, 0, 127, 5);
-                    UI_PrintStringSmallNormal(Credits, 0, 127, 6);
-            #else
-                    UI_PrintStringSmallNormal("Bandscope  ", 0, 127, 5);
-                    memcpy(gFrameBuffer[5] + 95, BITMAP_Ready, sizeof(BITMAP_Ready));
-
-                    #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
-                        UI_PrintStringSmallNormal("RescueOps  ", 0, 127, 6);
-                        if(gEeprom.MENU_LOCK == true) {
-                            memcpy(gFrameBuffer[6] + 95, BITMAP_Ready, sizeof(BITMAP_Ready));
-                        }
-                    #else
-                        UI_PrintStringSmallNormal("Broadcast  ", 0, 127, 6);
-                    #endif
-            #endif
-        #else
-            #ifdef ENABLE_FEAT_F4HWN_RESCUE_OPS
-                UI_PrintStringSmallNormal("RescueOps  ", 0, 127, 5);
-                if(gEeprom.MENU_LOCK == true) {
-                    memcpy(gFrameBuffer[5] + 95, BITMAP_Ready, sizeof(BITMAP_Ready));
-                }
-            #else
-                UI_PrintStringSmallNormal("Bandscope  ", 0, 127, 5);
-            #endif
-            UI_PrintStringSmallNormal("Broadcast  ", 0, 127, 6);
-            memcpy(gFrameBuffer[6] + 95, BITMAP_Ready, sizeof(BITMAP_Ready));
-        #endif
-        */
 #else
         UI_PrintStringSmallNormal(Version, 0, 127, 6);
 #endif
@@ -206,7 +222,7 @@ void UI_DisplayWelcome(void)
         ST7565_BlitFullScreen();
 
         #ifdef ENABLE_FEAT_F4HWN_SCREENSHOT
-            getScreenShot(true);
+            SCREENSHOT_Update(true);
         #endif
     }
-}
+}

App/usb/usbd_cdc_if.c

@@ -190,8 +190,13 @@ void cdc_acm_data_send_with_dtr(const uint8_t *buf, uint32_t size)
     {
         ep_tx_busy_flag = true;
         usbd_ep_start_write(CDC_IN_EP, buf, size);
-        while (ep_tx_busy_flag)
+        uint32_t timeout = 100000;
+        while (ep_tx_busy_flag && --timeout)
             ;
+        if (!timeout) {
+            ep_tx_busy_flag = false;
+            dtr_enable = 0;  // Consider USB disconnected
+        }
     }
 }
 

CMakePresets.json

@@ -60,16 +60,18 @@
                 "ENABLE_FEAT_F4HWN_RESCUE_OPS": false,
                 "ENABLE_FEAT_F4HWN_VOL": false,
                 "ENABLE_FEAT_F4HWN_AUDIO": false,
+                "ENABLE_FEAT_F4HWN_AUDIO_SCOPE": false,
                 "ENABLE_FEAT_F4HWN_RESET_VFO": true,
                 "ENABLE_FEAT_F4HWN_PMR": false,
                 "ENABLE_FEAT_F4HWN_GMRS_FRS_MURS": false,
                 "ENABLE_FEAT_F4HWN_CA": true,
                 "ENABLE_FEAT_F4HWN_DEBUG": false,
+                "ENABLE_FEAT_F4HWN_MEM": false,
                 "ENABLE_AGC_SHOW_DATA": false,
                 "ENABLE_UART_RW_BK_REGS": false,
                 "ENABLE_SWD": false,
                 "VERSION_STRING_1": "v0.22",
-                "VERSION_STRING_2": "v5.1.0"
+                "VERSION_STRING_2": "v5.3.0"
             }
         },
         {
@@ -188,6 +190,7 @@
                 "ENABLE_FEAT_F4HWN_RESCUE_OPS": true,
                 "ENABLE_FEAT_F4HWN_VOL": true,
                 "ENABLE_FEAT_F4HWN_AUDIO": true,
+                "ENABLE_FEAT_F4HWN_AUDIO_SCOPE": true,
                 "ENABLE_SWD": true,
                 "EDITION_STRING": "Fusion",
                 "TARGET": "f4hwn.fusion"

Core/py32f071xb.ld

@@ -145,6 +145,15 @@ SECTIONS
     _edata = .;        /* define a global symbol at data end */
   } >RAM AT> FLASH
 
+  /* Explicit placement of .noncacheable (CherryUSB) + end-of-FLASH symbol */
+  .noncacheable :
+  {
+    . = ALIGN(4);
+    *(.noncacheable)
+    *(.noncacheable*)
+    . = ALIGN(4);
+  } >RAM AT> FLASH
+  _eflash_used = LOADADDR(.noncacheable) + SIZEOF(.noncacheable);
   
   /* Uninitialized data section */
   . = ALIGN(4);

README.md

@@ -42,7 +42,7 @@ Anyway, have fun.
 
 # Donations
 
-Special thanks to Jean-Cyrille F6IWW (3 times), Fabrice 14RC123, David F4BPP, Olivier 14RC206, Frédéric F4ESO, Stéphane F5LGW (2 times), Jorge Ornelas (4 times), Laurent F4AXK, Christophe Morel, Clayton W0LED, Pierre Antoine F6FWB, Jean-Claude 14FRS3306, Thierry F4GVO, Eric F1NOU, PricelessToolkit, Ady M6NYJ, Tom McGovern (4 times), Joseph Roth, Pierre-Yves Colin, Frank DJ7FG, Marcel Testaz, Brian Frobisher, Yannick F4JFO, Paolo Bussola, Dirk DL8DF, Levente Szőke (2 times), Bernard-Michel Herrera, Jérôme Saintespes, Paul Davies, RS (3 times), Johan F4WAT, Robert Wörle, Rafael Sundorf, Paul Harker, Peter Fintl, Pascal F4ICR (2 times), Mike DL2MF (3 times), Eric KI1C (2 times), Phil G0ELM, Jérôme Lambert, Eliot Vedel, Alfonso EA7KDF, Jean-François F1EVM, Robert DC1RDB (2 times), Ian KE2CHJ, Daryl VK3AWA, Roberto Brunelli, Robert Boardman, Stephen Oliver, Nicolas F4INE, William Bruno, Daniel OK2VLK, Tayler Chew, Peter DL7RFP, Philippe Kopp, Rune LA6YMA, Jeremy Luna, Steef Wagenaar, Zhuo BG7SGA and Jamie M0JLB for their [donations](https://www.paypal.com/paypalme/F4HWN). That’s so kind of them. Thanks so much 🙏🏻
+Special thanks to Jean-Cyrille F6IWW (3 times), Fabrice 14RC123, David F4BPP, Olivier 14RC206, Frédéric F4ESO, Stéphane F5LGW (2 times), Jorge Ornelas (4 times), Laurent F4AXK, Christophe Morel, Clayton W0LED, Pierre Antoine F6FWB, Jean-Claude 14FRS3306, Thierry F4GVO, Eric F1NOU, PricelessToolkit, Ady M6NYJ, Tom McGovern (4 times), Joseph Roth, Pierre-Yves Colin, Frank DJ7FG, Marcel Testaz, Brian Frobisher, Yannick F4JFO, Paolo Bussola, Dirk DL8DF, Levente Szőke (2 times), Bernard-Michel Herrera, Jérôme Saintespes, Paul Davies, RS (3 times), Johan F4WAT, Robert Wörle, Rafael Sundorf, Paul Harker, Peter Fintl, Pascal F4ICR (2 times), Mike DL2MF (3 times), Eric KI1C (2 times), Phil G0ELM, Jérôme Lambert, Eliot Vedel, Alfonso EA7KDF, Jean-François F1EVM, Robert DC1RDB (2 times), Ian KE2CHJ, Daryl VK3AWA, Roberto Brunelli, Robert Boardman, Stephen Oliver, Nicolas F4INE, William Bruno, Daniel OK2VLK, Tayler Chew, Peter DL7RFP, Philippe Kopp, Rune LA6YMA, Jeremy Luna, Steef Wagenaar (2 times), Zhuo BG7SGA, Jamie M0JLB, Antoine LIBERT, Vince K0DKR, Julia DF7JA, Ken 2E0UMK, Victor TI2SYS, Tobi DG9LAY, Deaglan K4DFQ, Catherine PALMER and Brian WA6JFK for their [donations](https://www.paypal.com/paypalme/F4HWN). That’s so kind of them. Thanks so much 🙏🏻
 
 ## Table of Contents
 

tools/unbrick_k5_v1/README.md

@@ -2,11 +2,11 @@
 
 <img width="2016" height="1512" alt="pcbite" src="https://github.com/user-attachments/assets/b3086bf2-c14c-47da-b68b-a6867268ae78" />
 
-Restoring a UV-K5 V1 accidentally flashed with the F4HWN 4.3 Fusion 🔥 Edition firmware, using OpenOCD and a ST-LINK programmer.
+Restoring a UV-K5 V1 accidentally flashed with the F4HWN Fusion 🔥 Edition firmware, using OpenOCD and a ST-LINK programmer.
 
 ## Introduction
 
-Some users have accidentally flashed a UV-K5 V1 with the F4HWN 4.3 Fusion 🔥 Edition firmware. This edition **is only** compatible with:
+Some users have accidentally flashed a UV-K5 V1 with the F4HWN Fusion 🔥 Edition firmware. This edition **is only** compatible with:
 
 - UV-K5 V3
 - UV-K1