Internet of Things with Python

Reading pushbutton statuses with digital inputs and the mraa library

We will create a new PushButton class to represent a pushbutton connected to our board that can use either a pull-up or a pull-down resistor. The following lines show the code for the new PushButton class that works with the mraa library. The code file for the sample is iot_python_chapter_05_01.py.

import mraa import time from datetime import date class PushButton: def __init__(self, pin, pull_up=True): self.pin = pin self.pull_up = pull_up self.gpio = mraa.Gpio(pin) self.gpio.dir(mraa.DIR_IN) @property def is_pressed(self): push_button_status = self.gpio.read() if self.pull_up: # Pull-up resistor connected return push_button_status == 0 else: # Pull-down resistor connected return ...