How do you talk USB Power Delivery (PD)? Grab a PHY? Use a MCU with one built-in? Well, if you’re hardcore enough, you can do it with just a few resistors and GPIOs. [eeucalyptus] shows you their implementation of USB-PD on a CH32V003, which has no PD peripheral. This includes building a PD trigger, completely open source, and walking you through the entire low-level PD basics, too!
This is a companion discussion topic for the original entry at https://hackaday.com/2024/07/02/usb-pd-on-ch32v003-teaches-you-everything/