/Pico-PIO-USB

USB host/device implementation using PIO of raspberry pi pico (RP2040).

Primary LanguageCMIT LicenseMIT

Pico-PIO-USB

USB host/device implementation using PIO of raspberry pi pico (RP2040).

You can add additional USB port to RP2040.

🚧 This library is WIP. API may be changed drastically in future. 🚧

Demo

demo.mp4

Project status

Planned Features Status
FS Host ✔
LS Host ✔
Hub support ✔
Multi port ✔
FS Device ✔

Examples

  • capture_hid_report.c is a USB host sample program which print HID reports received from device. Open serial port and connect devices to pico. Default D+/D- is gp0/gp1. Call pio_usb_add_port() to use additional ports.
  • usb_device.c is a HID USB FS device sample which moves mouse cursor every 0.5s. External 1.5kohm pull-up register is necessary to D+ pin (Default is gp0).
cd example
mkdir build
cd build
cmake ..
make
# Copy UF2 file in capture_hid_report/ or usbdevice/ to RPiPico

Another sample program for split keyboard with QMK

https://github.com/sekigon-gonnoc/qmk_firmware/tree/rp2040/keyboards/pico_pico_usb

Resource Usage

  • Two PIO
    • One PIO is for USB transmitter using 22 instruction and one state machine
    • Another PIO is for USB receiver using 31 instruction and two state machine
  • Two GPIO for D+/D- (Series 22ohm resitors are better)
  • 15KB ROM and RAM
  • (For Host) One 1ms repeating timer
  • (For Device) One PIO IRQ for receiver