Raspberry Pi. Using node. js to control Gpio

40 Gpio on a Raspberry Pi is the best thing to play.

They can be directly controlled by c,/c++, Python, Java and other languages.

Now, let's see how to do the same thing with node. js.

Before you try, install node. js, and move to: < Raspberry Pi. Installation System +NODE.JS+MONGODB Series Environment >

1. Prepare the Test folder

mkdir/home/pi/documents/test-gpio-demo/

2. Create a file Package.json

{  "name":"Test-gpio-demo",  "version":"0.0.1",  "Dependencies":{    "Rpio2":"0.4.1"  }}

3. Create a Master file Blank.js

//Blink.jsConstGpio = require ('/home/pi/documents/test-gpio/node_modules/rpio2/lib/index.js'). Gpio;varLED =NewGpio ( $);//Create P36 PinLed.open (Gpio.output, gpio.low);//set to OUTPUT, default low for(vari =0; I < -; i++) {led.toggle (); //Toggle the level status of LEDsLed.sleep ( -);//wait 500ms}led.close ();

4. Hardware Circuit Connection

36th Foot (GPIO16) through a resistor (220 kohm or 1K), and then received the positive level of the LED

Led negative level to 34th foot (GND)

5. Trial run

Node/home/pi/documents/test-gpio-demo/blank.js

Flash Light Effect:

Bright Lights

Extinguishing lamp:

Test success!

=============================== Divider Line =========================

Rpio2 General Usage:

Synchronously

Const Gpio = require ('./lib/index.js'). Gpio; Const New Gpio (gpio.open); (gpio.output);  for (var0; i++) {    gpio.toggle ();    Gpio.sleep (+);} Gpio.close ();

Asynchronously

ConstGpio = require ('.. /lib/index.js'). Gpio;ConstGpio =NewGpio ( +); Gpio.open (gpio.output);voidfunction Loop () {Promise.resolve (Gpio.toggle ()). Then (Gpio.sleep.bind (NULL, -,true) . Then (Loop)} ();p Rocess.on ("SIGINT", function () {gpio.close (); Console.log ('shutdown!'); Process.exit (0);});

Toggle with button

ConstGpio = require ('.. /lib/index.js'). Gpio;Constbutton =NewGpio ( +);ConstOutput =NewGpio ( +); Button.open (gpio.input); Output.open (Gpio.output, Gpio.low) ;//Button downButton.on ('Rising', function () {output.toggle ();}); Process.on ("SIGINT", function () {button.close ();  Output.close (); Console.log ('shutdown!'); Process.exit (0);});

Raspberry Pi. Using node. js to control Gpio