mckero
ff14dffb67
The blank screen was self-inflicted and the earlier explanation was wrong. The FMP3 marker at 0x100000 is an ordinary state record -- generation, image_size, image_crc32, firmware_slot/slot_inv, config_bank/bank_inv and a matching state_crc32 (0x661286F1) -- not a pending flag. What actually happened: a firmware uploaded over a state that recorded a different identity made the firmware take the restore/adopt path, which draws nothing (panel 1024/1024 bytes zero) while the serial banner printed normally. Restoring the untouched dump fixed it at once (485/1024 bytes lit) and the three apps reinstalled and were confirmed by 0x0730. Clearing the marker sectors was tried twice (a whole 8 KiB, then just the 24-byte headers) and is not a fix: it sends the firmware down MB_MARK_MISSING = fresh radio, which adopts the running firmware slowly and without drawing, and its own write-back restores the marker anyway. AGENTS.md and AGENTS.zh-CN.md now say so in place of the wrong claim. apps/minesweeper/ adds our own 9x9 minesweeper for the 4 KiB overlay: no left/right keys exist on this radio (so the cursor walks with UP/DOWN and digits pick a row then a column), 81 cells need three 9-byte bit arrays rather than a uint16_t mask (the uint16_t version compiled fine and was wrong past cell 15), mines are placed after the first reveal so it cannot lose immediately, and the source compiles clean under gcc -Wall -Wextra -Werror against upstream's real app_api.h. It has not been built for ARM or run -- no toolchain here -- and the README says so.
Minesweeper — an overlay app for the F4HWN Labs edition
Our own app: a 9x9 minesweeper that runs on the radio inside the 4 KiB overlay that
App/apps/app_overlay.h reserves. It is written against upstream's App/apps/app_api.h
and built with upstream's app.ld — neither is vendored here (both are Apache-2.0
files from armel/uv-k1-k5v3-firmware-custom),
so drop this folder into App/apps/minesweeper/ next to them, or point -I at a copy.
Why it looks the way it does
| constraint | consequence |
|---|---|
| the radio has no left/right keys (UP, DOWN, MENU, EXIT, STAR, F, 0-9 only) | the cursor walks the field with UP/DOWN and digits jump to a row then a column: 3 5 = row 3, column 5 |
| 4 KiB for text+rodata+data+bss together | no lookup tables, no floats, no libc; adjacency is counted on the fly and each cell is one bit |
| 81 cells do not fit a 16-bit mask | three 9-byte bit arrays addressed by cell >> 3, cell & 7 — a uint16_t version compiled fine and was wrong past cell 15 |
| the resident pixel helpers do not bound-check | put()/invert() clip |
no rand() in a freestanding blob |
a small LCG; mines are placed after the first reveal, keeping the 3x3 around it clear |
Keys: UP/DOWN move, 1-9 pick row then column, MENU reveal, F flag, STAR new game,
EXIT quit. M in the corner is the remaining-mine count, A1 is the cursor.
Build
arm-none-eabi-gcc -mcpu=cortex-m0plus -mthumb -Os -std=gnu11 -ffreestanding \
-nostdlib -nostartfiles -T app.ld -Wl,--defsym,APP_VMA=0x20000280 \
-o minesweeper.elf minesweeper_app.c
arm-none-eabi-objcopy -O binary minesweeper.elf minesweeper.bin
pack_app.py minesweeper.bin Minesweeper.app --name Minesweeper --ver 1.0 \
--vma 0x20000280 --api-min 1 # pack_app.py lives in App/apps/
build.sh does exactly that and needs the Arm GNU Toolchain on PATH.
Then install it from the page: Overlay apps → a slot → pick Minesweeper.app →
Install → Ask the radio should answer Minesweeper. On the radio press
F then 7 and MENU to run it.
What is verified, and what is not
Verified here: the source compiles clean with gcc -Wall -Wextra -Werror against
upstream's real app_api.h (that check caught the API's actual member names —
api->fb, print_tiny(s, x, y, statusbar, fill) with five arguments — and the fact
that APP_KEY_LEFT/APP_KEY_RIGHT do not exist).
Not verified: it has never been built for ARM or run on the radio, because no
arm-none-eabi-gcc and no Docker exist on the machine it was written on. Treat the
first build and the first run as the real review.