IOsetting
Bit-Banged usb?
Do you think that bit-banging USB 1.0 is possible with this MCU? I did a quick search of repositories on github and I found this: https://github.com/xobs/grainuum https://github.com/ads830e/stm32f030-vusb https://github.com/lemcu/LemcUSB I think only in the possibilities of a usb bootloader in this small chip. CNLohr was doing this with the CH32V003: https://github.com/cnlohr/rv003usb This is the video of his project: https://www.youtube.com/watch?v=j-QazXghkLY
BTW the boards that i designed just arrived today. Tomorrow I will solder some of them and I will test the design.
That's impressive! I guess it is possible, considering that the emulation appears to be based on GPIO and EXTI.
Please have a look at my attempt in cnlohr/rv003usb#77. At the moment I'm not sure if pulling in a whole (if minimal) USB stack into py32f0-template is a good idea. On the other hand, @cnlohr's project is specifically for the CH32V003. Anyway I'm open to suggestions and comments.
For ARM based systems, grainuum is much more for you even though it is much less complete than rv003usb.
One warning, you will need to operate at 48MHz
But graniuum is not very complete (like you already said) and doesn't have many examples as the rv003usb. I think that if is possible to port the core of the rv003usb to the py32f002 the benefits of the port can make a big boost to this community.
Does the py32f002 operate reliably at 48MHz? If so you have a shot. If not, it would be virtually impossible to do in a generic way that does not have a lot of compromises that would be really painful.