Hardware & IoTLesson 99Free preview

RasPi GPIO Introduction

This lesson is part of Node.js · All levels

Summary

This lesson introduces GPIO programming from Node.js, specifically with the onoff or rpi-gpio library. You'll learn to set the pin direction, write the HIGH/LOW values, and read the status of the button. This foundation became the capital for all the sensor and actuator projects on Raspberry Pi.

Key points

Install the GPIO library as onoff.
New Gpio(pin, direction) makes the object pin; 'out' to write, 'in' to read.
Pin.write(1/0) turn on/off; pin.read() read the value (0/1).
It is mandatory to call unexport() when finished so that the pins are released back into the system.
Use a pull-up/pull-down resistor to keep the input from floating.

Full lesson

Code examples and quizzes

Full lessons, code examples, and quizzes are available to subscribers. 5 questions.