WCH CH32F203 EVT Board User Manual

1. Introduction

The WCH CH32F203 EVT Board is an industrial-grade enhanced low-power general-purpose Microcontroller Unit (MCU) evaluation board based on the high-performance Cortex-M3 core. Designed for a wide range of applications, the CH32F203 MCU operates at a system clock frequency of up to 144MHz and integrates a rich set of peripheral resources.

Key features include a 1-channel USB interface supporting USB Device functions, a 1-channel CAN interface (2.0B active), 2 Operational Amplifiers (OPAs), 3 U(S)ARTs, 2 IIC interfaces, 12-bit ADC, and 10-channel Touchkey capabilities. These features make the CH32F203 EVT Board suitable for various embedded development projects requiring robust performance and diverse connectivity options.

2. Key Features

The CH32F203 MCU boasts a comprehensive set of features designed for high-performance and low-power applications:

• Cortex-M3 core, with a system clock frequency up to 144MHz.
• Single-cycle multiplication and hardware division for efficient computation.
• Memory: 32KB SRAM, 128KB Flash.
• Wide supply voltage range: 2.4V to 3.6V.
• Multiple low-power modes: Sleep, Stop, and Standby for energy efficiency.
• Integrated Power-on/Power-down Reset (POR/PDR) and programmable voltage detector (PVD).
• 18-channel general-purpose DMA (Direct Memory Access).
• 2 operational amplifier comparators (OPA).
• 10-channel 12-bit ADC converters and 10-channel TouchKey support.
• 4 timers for precise timing and control.
• One USB2.0 full-speed device interface.
• 3 U(S)ARTs (Universal Synchronous/Asynchronous Receiver/Transmitter).
• One CAN interface (2.0B active) for robust communication.
• 2 IIC (Inter-Integrated Circuit) interfaces and 2 SPI (Serial Peripheral Interface) interfaces.
• 37 I/O ports, configurable for up to 16 external interrupts.
• CRC (Cyclic Redundancy Check) calculation unit and a 96-bit unique ID.
• Serial 2-wire debug interface for easy development and debugging.

3. Setup and Hardware Overview

This section details the hardware components of the CH32F203 EVT Board, available in two main variants: R0 and R1.

3.1. CH32F203CBT6-EVT-R0 Board

The R0 board features a compact design with essential interfaces. Refer to the table below for component descriptions:

3.2. CH32F203CBT6-EVT-R1 Board

The R1 board offers additional peripherals for more complex development. Refer to the table below for component descriptions:

4. Operating Instructions

4.1. In-Circuit Debug and Download (SWD)

For debugging and programming the CH32F203 EVT boards, the WCH-Link debugger is recommended. The Serial Wire Debug (SWD) interface is used for this purpose. The connection typically requires four lines:

• VCC: Power line
• GND: Ground line
• SWDIO: Data line
• SWCLK: Clock line

Ensure proper connection between the WCH-Link and the evaluation board as illustrated in the diagram below. The target board provides a 3V power interface for the debugger.

The MCU pinout diagram provides details on the various pins and their functions, which is crucial for advanced debugging and peripheral connections.

4.2. Available Routines

The CH32F203 EVT Board comes with a variety of routines to help developers get started and explore the MCU's capabilities. These routines cover a wide range of functionalities:

• External interrupt line routine
• FLASH erase/read/write, and fast program routines
• GPIO (General Purpose Input/Output) routines
• I2C-7/10bit addressing mode routines
• Low-power mode (Sleep/Standby/Stop) routines
• Clock source selection / MCO clock output routines
• SPI single-wire half-duplex/2-wire full-duplex modes routines
• Calendar routine
• Complementary output and dead time insertion mode routines
• External trigger routine for synchronous timer starts
• Input capture / single-pulse output / output compare / PWM output routines
• Reset/gate/trigger slave mode routines
• Timer routines using DMA
• TouchKey detection routine
• USART DMA/half-duplex/hardware flow control/interrupt/multi-processor communication/polling transceiver/serial port print debug/synchronization routines
• USB USBHD/ DEVICE device enumeration routines
• WWDG (Window Watchdog) routine
• Independent watchdog routine

These routines serve as excellent starting points for developing custom applications and understanding the MCU's peripherals.

5. Maintenance

To ensure the longevity and optimal performance of your CH32F203 EVT Board, follow these general maintenance guidelines:

• Handling: Always handle the board by its edges to avoid touching components, especially the sensitive pins and ICs.
• Storage: Store the board in an anti-static bag when not in use to protect it from electrostatic discharge (ESD). Keep it in a dry, cool environment away from direct sunlight and extreme temperatures.
• Cleaning: If necessary, gently clean the board with a soft, dry brush or compressed air to remove dust. Avoid using liquids or abrasive cleaners.
• Power Supply: Use a stable and appropriate power supply (2.4-3.6V) as specified in the features. Incorrect voltage can damage the MCU.
• Connections: Ensure all connections (USB, SWD, peripheral headers) are secure and correctly oriented before applying power.

6. Troubleshooting

This section provides basic troubleshooting steps for common issues you might encounter with the CH32F203 EVT Board.

6.1. Common Issues and Solutions

• Board not powering on:
  • Check the power supply connection and ensure it provides the correct voltage (2.4-3.6V).
  • Verify the power switch (if present on your board variant) is in the 'ON' position.
  • Inspect for any visible damage to the power input or components.
• Program download/debug failure:
  • Ensure the WCH-Link debugger is correctly connected to the SWD interface (VCC, GND, SWDIO, SWCLK).
  • Verify that the WCH-Link drivers are installed correctly on your computer.
  • Check your development environment settings (e.g., MounRiver Studio) for correct debugger selection and target device.
  • Confirm the boot mode configuration pins (BOOT0/1) are set correctly for programming.
• Peripheral not responding:
  • Double-check your wiring to the peripheral.
  • Review the MCU's datasheet and reference manual to ensure correct pin assignments and peripheral initialization in your code.
  • Test with known working example routines if available for that peripheral.

For more detailed troubleshooting, refer to the technical resources listed in Section 9.

7. Specifications

7.1. MCU Specifications (CH32F203CBT6)

7.2. Physical Dimensions

The board dimensions vary slightly between the R0 and R1 versions. The MCU package information is also provided.

Board Thickness: 1.6mm

CH32F203CBT6-EVT-R0 Board Dimensions: Approximately 45.675mm (Length) x 51.107mm (Width)

CH32F203CBT6-EVT-R1 Board Dimensions: Approximately 85.7mm (Length) x 67.3mm (Width)

8. User Tips

Based on common practices for development boards and similar MCUs, here are some tips for effective use:

• Start with Examples: Always begin by running the provided example routines to familiarize yourself with the MCU's peripherals and development environment.
• Consult Datasheets: For detailed information on registers, pin functions, and electrical characteristics, frequently refer to the CH32F203 datasheet.
• ESD Protection: Always use proper ESD (Electrostatic Discharge) precautions when handling the board to prevent damage to sensitive components.
• Power Management: Experiment with the low-power modes (Sleep, Stop, Standby) to optimize your applications for energy efficiency, especially for battery-powered projects.
• Community Support: Engage with online forums or communities related to WCH MCUs or Cortex-M3 development for shared knowledge and troubleshooting assistance.

9. Technical Resources and Support

For further technical details, documentation, and software resources, please refer to the official WCH website and the following links:

• CH32F203 Datasheet: CH32F20xDS0.PDF
• CH32F203 Reference Manual: CH32FV2x_V3xRM.PDF
• CH32F203 Routines (Example Code): CH32F20xEVT.ZIP

For additional support or inquiries, please contact WCH Official Store directly.