hid_keyboard.py

# Emulate a USB keyboard with a MicroPython device such as Raspberry Pico.

import pyb

# Microsoft
VENDOR_ID = 0x045e
# Keyboard
PRODUCT_ID = 0xfff8

# The default pins for I2C0 are SDA=GP4, SCL=GP5.
I2C_BUS = 0
I2C_ADDR = 0xB2


def press_key(key_code, delay_ms=100):
    # Key down
    keyboard.send(bytes([0x00, key_code, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]))
    pyb.delay(delay_ms)
    # Key up
    keyboard.send(bytes([0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00]))

    
# Setup the USB of the board such that it can be used to emulate a USB HID
# representing a keyboard.
pyb.usb_mode('HID', vid=VENDOR_ID, pid=PRODUCT_ID, hid=pyb.hid_keyboard, high_speed=False)

keyboard = pyb.USB_HID()

i2c = pyb.I2C(I2C_BUS, pyb.I2C.PERIPHERAL, addr=I2C_ADDR)

# Get keycodes from the I2C controller and make them key presses.
while True:
    try:
        data = i2c.recv(1, timeout=100)
    except:
        continue

    if data:
        key_code = data[0]
        press_key(key_code)