CH341A I2C Programming (Windows API)

CH341A is an USB interface chip that can emulate UART communication, standard parallel port interface, parallel communication and synchronous serial (I2C, SPI). The chip is manufactured by Chinese company Jiangsu QinHeng Ltd.

CH341A is used by some cheap memory programmers. The IC is somehow limited in this configuration, because the programmer makes use only of the SPI and I2C interface. A popular device is the so-called "CH341A MiniProgrammer" that you can buy for 2 to 5 USD. And this is probably the cheapest device using CH341A.

If you got a "MiniProgrammer", you may want to use for more than memory chips programming. The device can actually be used as USB to I2C converter (not only I2C, but this article will focus only on I2C function). Let's see how to use the included library and header to communicate with I2C devices.

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