Hardware items:
- Blue pill with STM32F103C8T6
- El cheapo ST-link USB adapter
- USB UART with 3v3 voltage levels
Connect the BluePill board with the ST-Link as follows
| ST-Link | BluePill | Wire Color |
|---|---|---|
| 3.3V | 3V3 | Red |
| SWDIO | DIO | Orange |
| SWCLK | DCLK | Brown |
| GND | GND | Black |
Based on Lup Yuen Lee's article here.
Connect the UART to USART 2
| UART | BluePill | Wire Color |
|---|---|---|
| RxD | PA2 (UART2 TX2) | Yellow |
| TxD | PA3 (UART2 RX2) | Blue |
| GND | GND | Black |
Check out the latest version of RIOT OS in the parent directory.
git clone git://github.com/RIOT-OS/RIOT.git
Create a Makefile that identifies the following:
- RIOT OS basedit
- Board type
- ST-LINK version (STLINK_VERSION)
- RSRT value for the onboard reset
Serial output:
- via: UART2 (PA2: Tx, PA3: Rx)
- settings: 115200 8N1
Compile the program via: make
Run it via: make flash
Flashing can pose some problems because the RST isn't connected. When you have problems with flashing try the following. Press the reset button on the Bluepill when you issue make flash and release it when openocd tries to connect. You only have to do this once per power-cycle of the Bluepill.
View the output via: make term