STM32F103C8(1.68USD BluePill board)+ChibiOS+USB example

Get

git clone --recursive https://github.com/rrozestw/ChibiOS-BluePillUSB.git

Fix hardware

Blue Pill board has wrong and a very simple USB circuit (e.g. reset is not supported).

Check R10 resistance; USB spec says there should be 1.5k pull. If you have 10k, like I do: add 2k resistor between 3.3V and P12.

Build

Run make

Flash using STLink v2

Run ./BURN.sh:

openocd -f bluepill.cfg -c 'init_reset halt; program build/ch.bin 0x8000000 verify;'

Flash using Black Magic Probe

arm-none-eabi-gdb -nx --batch \
  -ex 'target extended-remote /dev/ttyACM0' \
  -ex 'monitor swdp_scan' \
  -ex 'attach 1' \
  -ex 'load' \
  -ex 'compare-sections' \
  -ex 'kill' \
  build/ch.elf

Debug

Terminal 1:

arm-none-eabi-gdb --eval-command="target remote localhost:3333" ./build/ch.elf

Type in gdb to set breakpoint: b main

Terminal 2:

telnet localhost 4444

Execute command over telnet: > reset init

Terminal 1:

Continue in gdb: c

Run

sudo screen /dev/ttyACM0 115200

> help

ch> help
Commands: help exit info echo systime mem threads test write
ch> info
Kernel:       5.0.0
Compiler:     GCC 4.9.3 20150529 (prerelease)
Architecture: ARMv7-M
Core Variant: Cortex-M3
Port Info:    Advanced kernel mode
Platform:     STM32F10x Performance Line Medium Density
Board:        STM32F103 Minimal Module
Build time:   Dec  3 2017 - 21:16:29
ch> threads
stklimit    stack     addr refs prio     state         name

00000000 200007B4 20001D28    1  128    WTEXIT         main
20001528 20001574 200015B8    1    1     READY         idle
200013C8 2000146C 200014C8    1  128  SLEEPING      blinker
20001DF8 2000256C 20002678    1  129   CURRENT        shell
ch>