notes
Patrick Yang is a technical director at WCH. 南京沁恒 Here are some links. openwch github RISC-V based microcontrollers. CH32V003 32bit 48MHz 16KB flash, it is less than $0.5 for example. Arduino-wch58x. Another CH32V project. Flipping dots Kicad panelizing tool KiKit. This 3D printing uses UTR-8100 transparent amterial, from PCBWay.