Folks from [Adafruit] are displaying off a neat hack – USB host on RP2040, working with the now-renowned PIO peripheral. [Adafruit] builds a whole lot of RP2040 boards, and by natural means, you gotta test them in advance of you ship them to shoppers. They’ve been employing extremely particular Teensies for that, and at some position, those grew to become unobtainium. Based mostly on the get the job done of [sekigon-gonnoc] and with help of [Thach], they’ve produced their TinyUSB library aid bitbanging of USB around PIO, and properly ported their examination jig firmware to it!
The base Pico-PIO-USB repo by [sekigon-gonnoc] reveals a rather outstanding point out of affairs – with lower-pace and entire-velocity USB host and comprehensive-pace USB system modes supported, and pretty a couple examples to get you started off. [Adafruit]’s perform integrates this code into their TinyUSB stack, precisely focusing on MST (mass storage) characteristics – as this is what you need to program a RP2040. Of training course, they also provide a mass storage illustration to boot!
Check jigs are very crucial to have when creating several pieces of a board, and with RP2040 supporting extra and much more interfaces thanks to PIO, it appears like the fantastic chip for your subsequent output tests-meant PCB. With the jig brains taken care of, you will want to look into setting up no less important mechanical element, and we’ve lined rather a number of means to type that out – here’s an OpenSCAD script that generates lasercutting files out of KiCad boards, or a jig designed out of scrap copperclad FR4, and a rather comprehensive tutorial on building your possess lasercuttable jigs, to boot.
