gamepad – Button handling in the background

class gamepad.GamePad(b1: digitalio.DigitalInOut, b2: digitalio.DigitalInOut, b3: digitalio.DigitalInOut, b4: digitalio.DigitalInOut, b5: digitalio.DigitalInOut, b6: digitalio.DigitalInOut, b7: digitalio.DigitalInOut, b8: digitalio.DigitalInOut)

Scan buttons for presses

Usage:

import board
import digitalio
import gamepad
import time

B_UP = 1 << 0
B_DOWN = 1 << 1


pad = gamepad.GamePad(
    digitalio.DigitalInOut(board.D10),
    digitalio.DigitalInOut(board.D11),
)

y = 0
while True:
    buttons = pad.get_pressed()
    if buttons & B_UP:
        y -= 1
        print(y)
    elif buttons & B_DOWN:
        y += 1
        print(y)
    time.sleep(0.1)
    while buttons:
        # Wait for all buttons to be released.
        buttons = pad.get_pressed()
        time.sleep(0.1)

Initializes button scanning routines.

The b1-b8 parameters are DigitalInOut objects, which immediately get switched to input with a pull-up, (unless they already were set to pull-down, in which case they remain so), and then scanned regularly for button presses. The order is the same as the order of bits returned by the get_pressed function. You can re-initialize it with different keys, then the new object will replace the previous one.

The basic feature required here is the ability to poll the keys at regular intervals (so that de-bouncing is consistent) and fast enough (so that we don’t miss short button presses) while at the same time letting the user code run normally, call blocking functions and wait on delays.

They button presses are accumulated, until the get_pressed method is called, at which point the button state is cleared, and the new button presses start to be recorded.

get_pressed(self) → int

Get the status of buttons pressed since the last call and clear it.

Returns an 8-bit number, with bits that correspond to buttons, which have been pressed (or held down) since the last call to this function set to 1, and the remaining bits set to 0. Then it clears the button state, so that new button presses (or buttons that are held down) can be recorded for the next call.

deinit(self) → None

Disable button scanning.