Control, read, and monitor Linux GPIO devices from node.js.
A little set of interrupt-supporting wrappers around "/sys/class/gpio"
interface, to control pins on e.g. the Raspberry Pi or Beaglebone, as originally written to help get node-nrf off the ground.
It's synchronous/blocking because I forget why (probably to match Tessel?)
First add a jumper wire from GPIO pin 17 to GPIO pin 22, and npm install pi-pins
. Then:
var pin1 = require("pi-pins").connect(17),
pin2 = require("pi-pins").connect(22);
pin2.mode('in');
pin1.mode('high'); console.log("Should be true:", pin2.value());
pin1.mode('low'); console.log("Should be false:", pin2.value());
pin2.on('rise', function () { // …or `'fall'`, or `'both'`
console.log("RING A DING A LING");
});
pin2.value(true);
Here are its methods:
var GPIO = require('pi-pins');
— import suggestion, used belowvar pin = GPIO.connect(number)
— get pin ready for use. Could very possibly fail if you don't usesudo
to run your script or set perms or whatever. but then, the software and hardware, working together, as one, until the very endpin.mode(direction)
— set pin direction to'in'
or'out'
(or go straight to'low'
or'high'
output)pin.value()
— read the pin's value ('in'
mode)pin.value(boolean)
— set the pin's value ('out'
mode)
It also does events (parties, weddings):
'rise'
— emitted whengpio.value()
goes fromfalse
totrue
'fall'
— emitted whengpio.value()
goes fromtrue
tofalse
'both'
— emitted whenevergpio.value()
changes
If a tree might fall/rise/both in the forest and nobody is watching, neither is pi-pins
.
I sure hope not. But otherwise:
Copyright (c) 2013–2014, Nathan Vander Wilt
Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.
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