Pico-PIO-USB VS picodvi

I know that I can have multiple ports using https://github.com/sekigon-gonnoc/Pico-PIO-USB, but I wanted to know if I could make one port a device and the other a host at the same time using the given PIOs and state machines.

I think a PIO based USB driver is a better approach, but someone needs to do the work of porting that to Ada.

That would be Pico-PIO-USB library or some people combine two Pico boards (or one board with two RP2040 MCUs).

If you need both device and host interfaces at the same time, then you can either use Pico-PIO-USB library or combine two Pico boards (or one board with two RP2040 MCUs).

However, not so many microcontrollers can easily do USB keyboard input (host) and output (device) at the same time, if that's what you need. You could look at the Teensy 4 or Teensy 4.1 for example. There might be other Arduino-compatible boards that can do it, I'm not sure which. Apparently it's also possible on the Pi Pico with this project: sekigon-gonnoc/Pico-PIO-USB: USB host/device implementation using PIO of raspberry pi pico (RP2040). But that's a bit of an advanced hack, and I can't tell you how well it works.

Maybe you could use something like this: https://github.com/sekigon-gonnoc/Pico-PIO-USB

you should check out https://github.com/sekigon-gonnoc/Pico-PIO-USB for someone that has implemented USB chaining with rp2040. unfortunately it uses up both PIOs.

The pico just seems to be a flexible cheap option for USB applications. An example https://github.com/sekigon-gonnoc/Pico-PIO-USB

Highly experimental for advanced users. Adds a second USB port to Pi Pico using the PIO controller so the pico can connect to a PC and keyboard at the same time. https://github.com/sekigon-gonnoc/Pico-PIO-USB

watch the video to see this non-qmk firmware for the Rasberry pi Pico used to daisy chain devices with fixed device and host ports https://github.com/sekigon-gonnoc/Pico-PIO-USB

The RP2040 is a great MCU for playing with graphics as it can bit bang VGA and DVI/HDMI. There's some info on the DVI here: https://github.com/Wren6991/PicoDVI

I wrote a couple of articles on how to do bit banged VGA on the RP2040 from scratch: https://gregchadwick.co.uk/blog/playing-with-the-pico-pt5/ and https://gregchadwick.co.uk/blog/playing-with-the-pico-pt6/ plus an intro to PIO https://gregchadwick.co.uk/blog/playing-with-the-pico-pt4/

A few years back someone was bit banging DVI and 720p 30fps video straight off the RP2040 GPIO pins with just inline resistors between not and the HDMI cable.

https://github.com/Wren6991/PicoDVI

I have the Adafruit DVI board and have been hacking on it some. It's more fun than should be allowed.

There's a project to get this running using Rust[1]. Currently it outputs the blue channel with sync, but has trouble with the other two channels. I don't have a hardware lab with scope, logic analyzer, etc., so it's not easy for me to debug.

In the meantime, I've been doing some experiments in the C codebase as well[2], mostly in the direction of proportionally spaced bitmap text, using the fonts in the X11 distribution.

[1]: https://github.com/DusterTheFirst/pico-dvi-rs

[2]: https://github.com/Wren6991/PicoDVI/pull/48

There is even bit-banged DVI library for pico.

Apparently, there is a digital video output project for the RP2040 already out there [0]! As for why digital video is more rare, it is because the common digital video formats are higher bandwidth and require higher signal integrity.

[0] https://github.com/Wren6991/PicoDVI

I've seen people implement DVI with PIO, and I'm sure basic missile commands wouldn't be as bandwidth-intensive as that.

For example this guy (https://github.com/Wren6991/PicoDVI) essentially 'bit bangs' CML. Sure its not a completely compliant implementation, but it's pretty close... In his case using a push pull with 3.3V/0V. I don't know how he's getting a 0.8V swing.