Open Source Debugging Tool: High-Speed USB to UART, SPI, I2C, JTAG

In the previous article on dynamic library encapsulation examples, a CH347 high-speed USB to UART, SPI, I2C, JTAG bridging module was used, which is now open source 👉 GitHub Repository^[1].

Introduction

CH347 USB High Speed Bridge is a debugging tool designed based on the CH347^[2] chip, supporting high-speed USB, allowing USB to UART, USB to SPI, USB to I2C, USB JTAG, and USB to GPIO functionalities.

Features

Overview

• Type-C interface, USB2.0, supports 480Mbps high-speed mode
• Button to switch work modes, supports hot swapping, no need to unplug USB
• Built-in EEPROM, configurable working mode, chip VID, PID, maximum current value, vendor and product information strings, etc.
• Onboard high-efficiency DCDC, supports 5V, 3.3V power output, maximum 1A current, with short circuit protection
• Compact size, space-saving, easy to use

UART

• Built-in firmware simulates standard serial port for upgrading original serial peripheral devices, or adding additional serial ports via USB
• Serial applications on Windows operating system are fully compatible without modification
• Hardware full-duplex serial port, with independent transmit and receive buffers, supporting baud rates from 1200bps to 9Mbps
• Serial port supports 8 data bits, odd, even, or no parity, and 1 or 2 stop bits
• Each serial port has a built-in 12K byte receive FIFO and 4K byte transmit FIFO
• Supports common MODEM control signals RTS, DTR, DCD, RI, DSR, CTS
• Supports CTS and RTS hardware automatic flow control
• Supports half-duplex, provides serial port sending status indication TNOW, can be used to control RS485 transmit-receive switching
• Supports RS232, RS485, RS422 interfaces through external level conversion devices

SPI

• Host/Master mode
• Provides SCS line, SCK/CLK line, MISO/SDI/DIN line, MOSI/SDO/DOUT four signal lines
• Supports 2 chip select signal lines, can operate 2 SPI interface devices in time division
• Supports 8-bit/16-bit data structure, supports MSB and LSB transmission
• Supports SPI modes 0/1/2/3, supports transmission frequency configuration, transmission frequency can reach 60MHz
• Supports hardware DMA for sending and receiving
• Can flexibly operate 4-wire interface FLASH, MCU, sensors, etc., using computer API

I2C

• Host/Master mode
• Provides SCL and SDA signal lines, supports 4 transmission speeds
• Can flexibly operate 2-wire interface A/D, D/A, EEPROM, and sensor devices using computer API

JTAG

• Host/Master mode
• Provides TMS line, TCK line, TDI line, TDO line, and TRST line (optional)
• Supports high-speed USB data transmission
• Can flexibly operate CPU, DSP, FPGA, CPLD, MCU devices using computer API

GPIO

• Supports up to 8 GPIO input/output functionalities

Working Modes

K1 and K2 pressed output low level, released output high level. The table below ‘0’ indicates pressed, ‘1’ indicates released.

Switching working modes:

The default is mode 0 when powered on; hold K1 and press RST to switch to mode 1; hold K2 and press RST to switch to mode 2; simultaneously hold K1 and K2 and press RST to switch to mode 3.

PINOUT

Shell

Debug Records

1. CH347 Dynamic Library Encapsulation Example

Related Projects

• [WIP]CH347 Chip Python Library^[3]

Future work will continue to improve the Python software library and enrich its functionalities.

Currently, I have a few samples available, feel free to contact me if you need any.

References