Package Exports

perf-gpio

This package does not declare an exports field, so the exports above have been automatically detected and optimized by JSPM instead. If any package subpath is missing, it is recommended to post an issue to the original package (perf-gpio) to support the "exports" field. If that is not possible, create a JSPM override to customize the exports field for this package.

Readme

perf-gpio

High performance GPIO tool kit for raspberry pi, including quadrature_decoder, DC motor control, soft PWM, buttons, etc. Based on c wiringpi.

install

npm install perf-gpio --save

API Example

https://pinout.xyz/pinout/wiringpi# is the best doc I can find for wiringpi Pin number mappings.

onoff -- simple

var onoff = require('perf-gpio').onoff;

// wiring-pi 2 = GPIO27 = PIN13
var led = onoff(2);
led.set(1);

onoff -- flash

var onoff = require('perf-gpio').onoff;

// wiring-pi 2 = GPIO27 = PIN13
var led = onoff(2);

var current = false;

setTimeout(timeout, 1000);
function timeout() {
    setTimeout(timeout, 1000);
    current = !current;
    led.set(current);
    console.log(current);
}

button -- simple read

var button = require('perf-gpio').button;

// wiring-pi 3 = GPIO22 = PIN15
var b = button(3, button.PUD_UP); // use raspberry pi build-in 50k pull-up resistor

setTimeout(timeout, 1000);
function timeout() {
    setTimeout(timeout, 1000);
    var current = b.get();
    console.log(current);
}

button -- callback

var button = require('perf-gpio').button;

// wiring-pi 3 = GPIO22 = PIN15
var b = button(3, button.PUD_UP);

b.watch(function(err, status) {
    console.log(status? 'UP' : 'DOWN');
});

quadrature_decoder

var qd = require('perf-gpio').quadrature_decoder;

// quadrature_decoder you need 2 pins, phase A and B
// wiringpi PIN 0 and 1, maps to BCM GPIO 17 and 18
var counter = qd(0,1);

timeout();

function timeout() {
    setTimeout(timeout, 1000);
    console.log(counter.getCounter());
}

led (basic)

var pin = require('perf-gpio').led(25); // wiringPi 25, GPIO 26
pin(0.5); // 50% on

led (more complete)

var led = require('perf-gpio').led;
var pin = led(25); // wiringPi 25, GPIO 26
pin(1);

setTimeout(function() {
    pin(0.5);
    setTimeout(function() {
        pin.close(); // turn off led before quit
        led.shutdown(); // shutdown DMA device before quit
        process.exit(0);
    }, 2000);
}, 2000);

DC motor control

var motor = require('./index').motor;
// Need 2 pin to control a DC motor (forward/backword)
// you need a H-bridge module to drive a DC motor
var pin = motor(23, 25); 

pin(-0.5); // anywhere range from [-1.0, +1.0]

function timeout() {
    pin.close(); // turn off motor before quit
    motor.shutdown(); // shutdown DMA device before quit
    process.exit(0);
}

setTimeout(timeout, 2000);

How it works

Performance is the main reason I write this lib. perf-gpio is based on c wiringPi, most of the interrupt handling is done in c code. This is especially important for quadrature_decoder, so far perf-gpio is probably the best quadrature decoder available on raspberry-pi. And also perf-gpio is probably the only node.js gpio lib which supports pull-up/down resistors (which is a must-have for my project). DMA based Soft-PWM is based on rpio-pwm.

license

MIT