GPIO

CH341A USB to I2C / GPIO adapter

As you can see most of the pins are available on SPI interface, but D4 and D6 is missing. D6 can be found as RTS at the bottom of module.

Download and install the I2C/GPIO Linux kernel driver (This is a GPIO driver with some basic I2C functionality)

rmmod ch341
insmod i2c-ch341-usb.ko

Accessing GPIO pins from Linux

This example will show how it works with liting a led with writing 1 and turning off with 0.

echo out > /sys/class/gpio/gpio0/direction
echo 1 > /sys/class/gpio/gpio0/value

Each pin accessible separate Di = GPIOi at /sys/class/gpio.

Check all available settings at: https://github.com/gschorcht/i2c-ch341-usb