WALKIE ONE 06 - BOARD TEST FIRMWARE v1.0

Checks the status LED, buttons, speaker, microphone, fuel gauge, USB detect,
modem power-on and IMEI, SIM and signal, GNSS, the modem USB path and modem
power-off. It prints each result on the board's USB-C serial port and waits for
you wherever a person must look, listen or press.

Status: checked against the 06 schematic, NOT YET RUN ON A REAL 06 BOARD.

  WalkieOne06_Test_v1.0.bin   single image, flash at address 0x0
                              SHA-256 2583752e9da9dc5f0cd8c6fc2768f057ec0781e7ed5529ab41128537e9f6dafd
  WalkieOne06_Test/           Arduino source

FLASH
  pip install esptool
  esptool --chip esp32s3 -p <port> write-flash 0x0 WalkieOne06_Test_v1.0.bin
  If no port appears, hold BOOT, press and release RESET, release BOOT.
  Press RESET afterwards; the LED blinks green once.

RUN
  Open the serial port at 115200 baud and press Enter, then Enter again to run
  all 11 steps (or type a step number). Answer y or n; s skips an optional step.
  The firmware never powers the modem until you confirm the antennas are fitted.
  Build-Instructions.pdf explains each step.

BUILD FROM SOURCE
  arduino-cli with the esp32 core 3.3.11:
  arduino-cli compile --fqbn "esp32:esp32:esp32s3:FlashSize=16M,PSRAM=opi,FlashMode=qio,PartitionScheme=app3M_fat9M_16MB,CDCOnBoot=cdc,USBMode=hwcdc" WalkieOne06_Test
  Then merge bootloader (0x0), partitions (0x8000), boot_app0 (0xe000) and the
  app (0x10000) into one image with: esptool --chip esp32s3 merge-bin
