51 MCU development board

This is a personal project, going back in time a bit, as well as giving myself a new toy. I have been looking at this module for a while, and finally decided to give it a go... It has finally arrived, and out of the box seems of good quality. Documentation is however quite a pain to obtain, with most being in Chinese, and for a different version of the hardware ( I got a Rev 3.1 board, with only Rev 1.0 schematics being available on the internet). This was however expected and adds to the "fun" of hacking something like this... A multimeter in continuity mode does wonders to trace pins, and figuring out how to use the built-in peripherals and ultimately hacking them is definitely part of the fun of something like this. Thank you