digitalio

Basic digital pin support

The digitalio module contains classes to provide access to basic digital IO.

All classes change hardware state and should be deinitialized when they are no longer needed if the program continues after use. To do so, either call deinit() or use a context manager. See Lifetime and ContextManagers for more info.

For example:

import digitalio
from board import *

pin = digitalio.DigitalInOut(D13)
print(pin.value)

This example will initialize the the device, read value and then deinit() the hardware.

Here is blinky:

import digitalio
from board import *
import time

led = digitalio.DigitalInOut(D13)
led.direction = digitalio.Direction.OUTPUT
while True:
    led.value = True
    time.sleep(0.1)
    led.value = False
    time.sleep(0.1)

class digitalio.DigitalInOut(pin: microcontroller.Pin)

Digital input and output

A DigitalInOut is used to digitally control I/O pins. For analog control of a pin, see the analogio.AnalogIn and analogio.AnalogOut classes.

direction :Direction

The direction of the pin.

Setting this will use the defaults from the corresponding switch_to_input() or switch_to_output() method. If you want to set pull, value or drive mode prior to switching, then use those methods instead.

value :Bool

The digital logic level of the pin.

drive_mode :DriveMode

The pin drive mode. One of:

pull :Optional[Pull]

The pin pull direction. One of:

Raises

AttributeError – if direction is OUTPUT.

deinit(self)

Turn off the DigitalInOut and release the pin for other use.

__enter__(self)

No-op used by Context Managers.

__exit__(self)

Automatically deinitializes the hardware when exiting a context. See Lifetime and ContextManagers for more info.

switch_to_output(self, value: bool = False, drive_mode: digitalio.DriveMode = digitalio.DriveMode.PUSH_PULL)

Set the drive mode and value and then switch to writing out digital values.

Parameters

  • value (bool) – default value to set upon switching

  • drive_mode (DriveMode) – drive mode for the output

switch_to_input(self, pull: Pull = None)

Set the pull and then switch to read in digital values.

Parameters

pull (Pull) – pull configuration for the input

Example usage:

import digitalio
import board

switch = digitalio.DigitalInOut(board.SLIDE_SWITCH)
switch.switch_to_input(pull=digitalio.Pull.UP)
# Or, after switch_to_input
switch.pull = digitalio.Pull.UP
print(switch.value)
class digitalio.Direction

Defines the direction of a digital pin

INPUT :Any

Read digital data in

OUTPUT :Any

Write digital data out

class digitalio.DriveMode

Defines the drive mode of a digital pin

PUSH_PULL :Any

Output both high and low digital values

OPEN_DRAIN :Any

Output low digital values but go into high z for digital high. This is useful for i2c and other protocols that share a digital line.

class digitalio.Pull

Defines the pull of a digital input pin

UP :Any

When the input line isn’t being driven the pull up can pull the state of the line high so it reads as true.

DOWN :Any

When the input line isn’t being driven the pull down can pull the state of the line low so it reads as false.