WCH-DAPLink Debugger

# Introduction
This is a remade version of Qinheng's WCH-DAPLink. The schematic design and firmware come from [Qinheng official] (https://www.wch.cn/products/WCH-Link.html). Based on the DAP-Link v2 solution, it is driver-free and supports three interfaces: `JTAG`, `SWD` and `Serial Port`, which can be recognized by Keil and OpenOCD. Comprehensive functions and easy to use.
Based on the original design, this project further reduces the quantity and cost of materials, and optimizes component selection and layout by hand welding to make production more convenient. The USB Type A male connector is replaced with a USB Type C female connector, which is more convenient to use.
# The function
leads to `JTAG`, `SWD`, `serial port`, `+5v`, `3.3v` and `ground` through 2x5 2.54mm pin header, which can be used for debugging and external power supply.
The specific usage is no different from standard DA-Link.
Among them, the serial port only supports the following baud rates:
```
1200, 2400, 4800, 9600, 14400, 19200, 38400,
57600, 115200, 230400, 460800, 921600 ```
# Instructions for use
The DAP-Link of this project uses CH32V203 For microcontroller implementation, after welding is completed, the firmware needs to be burned before it can be used. The specific steps are as follows.
1. Complete the welding work
2. Short-circuit the BOOT interface of the debugger, plug in the USB and power on to enter the burning mode
3. Download the two attachments and decompress WCHISPTool_CH32Vxxx.rar
4. Enter the decompressed folder and follow the instructions in /Doc , select WCH-DAPLink_APP_IAP.bin and burn
5. Disconnect the BOOT interface, re-insert the USB, and you can use it normally
# Design optimization
If you feel that the material cost is still high, this design can be further optimized
1. If it is only used as a DAP-Link When used, the ModeS interface can be omitted
2. The two LEDs and their series resistors can be omitted
3. The LDO can be replaced with other 5v to 3.3v devices
4. The series resistor of the 2x5 pin header can be replaced with an approximate resistance
# Assemble the shell
Taobao search `USB You can find the casing, it probably looks like this! [IMG_20230521_183027.jpg] ![IMG_20230521_183019.jpg]
# Modification instructions
- Change the two buttons to 2.54mm pin headers
- Adjust the power supply layout and improve the integrity of the ground plane