hello-ch32v103

A simple "Hello World"-like project for the WCH CH32V103 RISC-V MCU.

This project contains a simple set of modules to get the MCU running in a minimal configuration:

• Serial I/O on USART1 (connected to WCH-Link VCP)
• SysTick enabled and using empty dummy interrupt handler
• TIM3 Channel 1 configured for PWM output to LED
• ADC1 internal temperature sensor and Vrefint readout
• I2C2 interface with 24C64 EEPROM read and write access

Requirements

• Hardware
  • WCH CH32V103R8T6-EVT-R1 Evaluation Kit (available from LCSC, PartNr C2943982) + USB-A to USB-C Cable
  • (optional) Female-female jumper wires
  • (optional) AT24C64 EEPROM IC + Solderless breadboard + 2x 10k Resistors
• Software
  • Linux OS or WSL installation
  • Docker Engine (running within WSL if applicable)
  • VSCode Dev Containers extension
  • (WSL only) usbipd-win

Hardware Setup (optional)

• Connect the LED1 and PA6 pins on header J3 using a female-female jumper wire
• Connect the 24C64 EEPROM to PB10 and PB11 and add 10k pull-up resistors to SDA and SCL:

       .___________.  VCC   VCC VCC       VCC  .________________
      1|    |_|    |8  |     |   |         |   |
   +---| A0    VCC |---+    .|. .|.        +---| VCC (3V3)
   |  2|           |7       | | | | R1,R2      |
   o---| A1     WP |---+    |_| |_| 10k    +---| GND
   |  3|           |6  |     |   |         |   |
   o---| A2    SCL |---(-----o---(---------(---| PB10 (I2C2_SCL)
   |  4|           |5  |         |         |   |
   o---| GND   SDA |---(---------o---------(---| PB11 (I2C2_SDA)
   |   |___________|   |                   |   |________________
  GND  U2             GND                 GND  U1
       AT24C64 (DIP8)                          CH32V103R8T6
  

Usage

• Clone this repository using the following command. Note the use of the --recursive tag.

  git clone --recursive https://github.com/islandcontroller/hello-ch32v103
  

• Open the folder in VSCode

• Connect WCH-Link debug probe

  • (WSL only) attach to WSL using usbipd attach --wsl --busid <...>. This needs to be completed before starting the Dev Container.

• Run the command "Dev Containers: Reopen in Container"

  • Check if the board is recognised as a connected USB device by running lsusb.

  • On first launch, you may need to install some udev rules on your host machine. Copy the files to your workspace by running setup-devcontainer inside the container.

  • Re-open the workspace on your host and run the install-rules script inside the .vscode/setup folder.

    cd .vscode/setup
    sudo ./install-rules
    

  • Afterwards, restart the devcontainer.

• If prompted, select the "[unspecified]" CMake Kit.

• Run "CMake: Configure"

• Build using "CMake: Build [F7]"

• Open a new terminal and launch the serial monitor:

  cu -l /dev/ttyACM0 -s 115200
  

  To close the connection later on, press ESC/ENTER, type ~. (tilde, dot) and wait for 3 seconds.

• Start debugging using "Debug: Start Debugging [F5]"

• Continue execution once the breakpoint in main() is reached.

• Type ? in the serial monitor Terminal tab to show available commands.

If you want to use the EEPROM demo, remove the comment at the start of the #define USE_EEPROM_DEMO line at the top of main.c. The demo is disabled by default.

WCH-Link Firmware Update

If the debugger fails to program the target device, try updating the firmware of your debugger. The wchisp utility is included in the package, and compatible firmware files are provided in the /opt/wch/firmware directory inside the container. See the WCH-Link User Manual for more information.

In order to update the on-board debugger on a CH32V103R-R1-1v1 eval board, follow the firmware update procedure:

• Disconnect the board from USB

• Short-circuit the pads of J1 usind pliers

• Re-connect the board via USB

• (WSL only) Re-attach the CH549 device to WSL

• Flash the firmware file

  wchisp flash /opt/wch/firmware/WCH-Link_APP_IAP_RV.bin
  

• Restart the board

Licensing

If not stated otherwise in the specific file, the contents of this project are licensed under the MIT License. The full license text is provided in the LICENSE file.

SPDX-License-Identifier: MIT

Help and References

• openwch/ch32v103 Manufacturer EVT demos and documentation
• WCH-IC: CH32V103DS0.pdf MCU Datasheet
• WCH-IC: CH32xRM.pdf MCU Reference Manual
• WCH-IC: QingKeV3_Processor_Manual.pdf Processor Core Manual

If you're looking for further information about WCH products, check out their community Discord server: