The most beggar 17+4+ touch mechanical keyboard PRO-hot plug version (CH552G)

Directly apply the motherboard drawing of Shengcai, replace the shaft seat with hot-swap, and make
subtle adjustments to the "+" and "ENTER" shaft seats by more than 90 rotations:
1. The third-generation default SL2.1A chip version, the boot key position has been fine-tuned, the highest position of the key is basically level with the PCB frame, which is convenient for disassembly and assembly of the PCB;
2. The third-generation HS8836A chip version, in addition to adjusting the boot key position, the 4 buttons on the top plate have also been fine-tuned downwards, and the adjustment range is small;
 
Firmware version problem:
V122 is the old version.
Versions after V192 support reconstruction
 
projects. Detailed introduction:
Shengcai original open source website link https://oshwhub.com/yangzen/xing-huo-ji-hua-zui-gai-17-4-chu-mo-ji-xie-jian-pan-pro
B station related tutorial video [Akiyama Xiangyangawa's personal space-Bilibili] https://b23.tv/g8pNueI
 
About hub chip:
1. The third-generation pad uses the SL2.1A chip by default, which requires an external crystal oscillator and is not very stable;
2. The optimized version of the third-generation pad uses the HS8836A chip, which does not require an external crystal oscillator. Compared with SL2.1A, it has two more resistors, 100K and 75R, and the resistance value is directly marked on the silk screen on the board;
 
Regarding the left shift of the top button:
the board has been verified, but the PCB is connected through the solder pad. During the disassembly and assembly process, the board will be disconnected and the solder pad will be lost due to elongation, so the connection method with a soft cable was changed, and then the shell was modified and the stl file was uploaded;
 
the shell was drawn by myself, suitable for fdm 3D printer printing, and the top 4 buttons are made of crispy