circuitpython/docs/zephyr/tutorial/pins.rst

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.. _pins_zephyr:
GPIO Pins
=========
Use :ref:`machine.Pin <machine.Pin>` to control I/O pins.
For Zephyr, pins are initialized using a tuple of port and pin number ``(\"GPIO_x\", pin#)``
for the ``id`` value. For example to initialize a pin for the red LED on a FRDM-k64 board::
LED = Pin(("GPIO_1", 22), Pin.OUT)
Reference your board's datasheet or Zephyr documentation for pin numbers, see below for more examples.
.. list-table:: Pin Formatting
:header-rows: 1
* - Board
- Pin
- Format
* - frdm_k64f
- Red LED = PTB22
- ("GPIO_1", 22)
* - 96b_carbon
- LED1 = PD2
- ("GPIOD", 2)
* - mimxrt685_evk_cm33
- Green LED = PIO0_14
- ("GPIO0", 14)
Interrupts
----------
The Zephyr port also supports interrupt handling for Pins using `machine.Pin.irq() <machine.Pin.irq>`.
To respond to Pin change IRQs run::
from machine import Pin
SW2 = Pin(("GPIO_2", 6), Pin.IN) # create Pin object for switch 2
SW3 = Pin(("GPIO_0", 4), Pin.IN) # create Pin object for switch 3
SW2.irq(lambda t: print("SW2 changed")) # print message when SW2 state is changed (triggers change IRQ)
SW3.irq(lambda t: print("SW3 changed")) # print message when SW3 state is changed (triggers change IRQ)
while True: # wait
pass