CONFIG_READ was being (ab)used by the Windows viewer's Live-Sync feature
to poll just the active profile every 1.5s, but the handler sends the
full 740-byte config as ~124 blocking chunk packets from inside
poll_vendor() -- which runs before updateLEDs() in the same loop
iteration (see the loop-order comment at the top of
CMainController.cpp). Every poll cycle stalled updateLEDs() long enough
that running Pulse/Blink animations visibly stuttered, since their
brightness is computed from an absolute millis() timestamp and jumps
forward once the stall clears instead of catching up smoothly.
Added USB_CMD_READ_STATUS (0x06) / USB_EVT_STATUS (0x86): a single NVM
read (no serial I/O) and one 8-byte reply packet with the active
profile in Data[1], no chunking. Documented in
doc/07_serial_protocol.md alongside why CONFIG_READ is unsuitable for
polling. CONFIG_READ stays as-is for actual full-dump use (e.g. "Vom
Board laden").
Verified on hardware after flashing via env:versapad_usb: READ_STATUS
returns the correct profile in ~well under CONFIG_READ's dump time,
Live-Sync no longer visibly disturbs LED animations.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
pio run -e versapad --target upload writes the app starting at
0x0000 and silently destroyed the installed UF2 bootloader twice
today during testing -- no warning, no error, just a board that
stopped responding to the boot-key hold.
upload_openocd.py now checks for the bootloader (verify_image against
the locally built bootloader/.pio/build/versapad_bootloader/firmware.bin)
before an env:versapad upload and refuses if one is present, pointing
at env:versapad_usb instead. Fails closed: an inconclusive check (e.g.
bootloader not built locally, SWD not responding) blocks rather than
proceeding on a guess -- confirmed necessary the hard way, since a
"fail open" first attempt let the destructive upload through silently.
Scoped to PIOENV == "versapad" only, since bootloader/platformio.ini's
own upload reuses this same script and must always be allowed to write
0x0000. A new erase-bootloader-and-flash custom target remains as the
explicit, deliberate override.
Documented the workflow (bootloader is its own PlatformIO project,
flashed once via SWD; versapad_usb is the normal path afterward;
versapad's upload is now guarded) in README.md and
doc/10_usb_bootloader.md.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Adds doc/10_usb_bootloader.md as the primary reference for the UF2
bootloader (memory layout, key-based boot entry, build/flash steps,
hardware test findings, known limitations), following the existing
numbered-doc convention. Updates doc/INDEX.md, doc/09_known_limitations.md
(bootloader is no longer "not supported", just scoped), and
doc/08_development.md accordingly.
Removes bootloader/TESTING.md (its findings now live in
doc/10_usb_bootloader.md) and trims bootloader/README.md down to what
belongs with that subproject specifically: upstream attribution/license
and local build/flash commands, plus the OpenOCD manual-flashing
warning since that's implementation-specific detail that would clutter
the higher-level doc.
Updates the top-level README.md (feature table, hardware table,
quickstart, project tree, doc links) to reflect USB flashing as a
supported path alongside SWD.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Adds uf2conv.py (minimal, dependency-free .bin -> .uf2 converter
matching bootloader/inc/uf2format.h's block layout) and upload_uf2.py,
a PlatformIO upload hook for env:versapad_usb that finds the mounted
VERSABOOT volume and copies the converted firmware onto it.
env:versapad_usb previously used upload_protocol=sam-ba, the classic
Arduino/Atmel protocol -- the actual bootloader speaks UF2/mass
storage, not SAM-BA, so that upload path never worked. Switched to
upload_protocol=custom with the new hook, and cleaned the now-unused
SAM-BA-specific fields out of boards/versapad.json.
Verified end to end on real hardware: pio run -e versapad_usb
--target upload builds, converts, copies to the VERSABOOT drive, and
the bootloader jumps into the freshly written app on its own.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Hardware-tested the UF2 bootloader end to end on a real VersaPad v2
board. Found and fixed a real bug: the bootloader's jump into the app
(__set_MSP -> SCB->VTOR -> bx) hard-faulted on every standalone boot,
even with the debugger fully disconnected; identical register/VTOR
values injected directly by a halted debugger ran fine, which pointed
at the missing __DSB()/__ISB() barriers ARM's own guidance requires
for this exact pattern. Also fixed a USB PID collision (0x0011 is
Adafruit's own Gemma M0 bootloader PID, misidentified by Windows as a
Circuit Playground COM port instead of exposing VERSABOOT).
This board has no dedicated reset/boot button, so add a hardware boot
entry that doesn't need one: holding the bottom-right Cherry MX key
(key_id 24) during reset/power-on drives its matrix row and reads its
column directly in the bootloader, before the app is even validated.
Also corrected the app-side flash_with_bootloader.ld (was missing the
NVM carve-out flash_without_bootloader.ld already has) and
boards/versapad.json (wrong flash/RAM size, wrong MCU macro, stale
PID), and enabled the previously-commented-out env:versapad_usb.
Documented findings in bootloader/README.md, bootloader/TESTING.md,
and doc/09_known_limitations.md.
Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
