https://www.gigadevice.com/microcontroller/gd32f303vgt6/
https://datasheet.lcsc.com/szlcsc/1809141330_Anlogic-EG4X20BG256_C134197.pdf
http://www.mxtronics.com/n107/n124/n181/n184/c692/attr/2630.pdf
DM1106EN multimeter chip
https://www.ti.com/lit/ds/symlink/dac904.pdf