When Hardware Met NodeJS

make web app faster

WEB SERVER

var http = require('http');
http.createServer(function (req, res) {
    res.writeHead(200, {'Content-Type': 'text/plain'});
    res.end('Hello World\n');
}).listen(1337, '127.0.0.1');
console.log('Server running at http://127.0.0.1:1337/');

## Arduino Uno($29.95)

[MAKE Volume 25: Arduino](http://www.youtube.com/watch?v=oVsDloC6DJY)

[The Inebriator](http://www.youtube.com/watch?v=hJIkJ9x0-JQ)

Low-cost ARM IS COMING

with high performance

## BeagleBone($89)

[Ninja Blocks use Beaglebone](http://www.youtube.com/watch?v=3RGRIS_Rqiw)

## Raspberry Pi($35)

(Model B now ships with 512MB of RAM)

[Quake 3 on Raspberry Pi](http://www.youtube.com/watch?v=e_mDuJuvZjI)

What if these hardware can be controlled by nodeJS?

If so, it could be easy to control hardware from website!

[Real-time Charting with HTML5](https://www.youtube.com/watch?v=va7j86thW5M)

So, how are they hook up with nodeJS?

Arduino + NodeJS

↓

## OK, LED FIRST

↓

### Make arduino skitch(code) first!

↓

Upload skitch to arduino

void setup() {
 Serial.begin(9600);

 // initialize the digital pin as an output.
 // Pin 13 has an LED connected on most Arduino boards:
 pinMode(13, OUTPUT);
}

void loop() {
  int incomingValue = 0;           // from nodeJS

  if ( Serial.available() > 0 ) {  // check the incoming value
    incomingValue = Serial.read();
  }

  if ( incomingValue == 49 ) {     // if the value is '1'
    digitalWrite(13, HIGH);        // turn on the light
  }

  if ( incomingValue == 48 ) {     // if the value is '0'
    digitalWrite(13, LOW);         // turn off the light
  }
}

### Then, make 어썸 JavaScript

↓

### Open the device ... var fs = require('fs'); // // Open /dev/tty-usbserial1 // fs.open('/dev/tty-usbserial1', 'a', 666, function( e, fd ) { // // must do something, huh? // });

### Send '1' to arduino var fs = require('fs'); fs.open('/dev/tty-usbserial1', 'a', 666, function( e, fd ) { // // send '1' // fs.write( fd, '1', null, null, null, function(){ // // do something, maybe // } });

### and close... var fs = require('fs'); fs.open('/dev/tty-usbserial1', 'a', 666, function( e, fd ) { fs.write( fd, '1', null, null, null, function(){ // // close the connection // fs.close(fd, function() { // // do something? really? // }); } });

fs.open... fs.write... fs.close...

Use the modules!

Dude, it's the 21 century.

## Hey, it's so many! choose some well-known

## OK Then, LED Again

↓

## Install duino module

npm install duino

## Upload skitch to arduino [https://github.com/ecto/duino/blob/master/src/du.ino](https://github.com/ecto/duino/blob/master/src/du.ino)

#include <Servo.h>

bool debug = false;

int index = 0;

char messageBuffer[12];
char cmd[3];
char pin[3];
char val[4];
char aux[4];

Servo servo;

void setup() {
  Serial.begin(115200);
}

void loop() {
  while(Serial.available() > 0) {
    char x = Serial.read();
    if (x == '!') index = 0;      // start
    else if (x == '.') process(); // end
    else messageBuffer[index++] = x;
  }
}

/*
 * Deal with a full message and determine function to call
 */
void process() {
  index = 0;

  strncpy(cmd, messageBuffer, 2);
  cmd[2] = '\0';
  strncpy(pin, messageBuffer + 2, 2);
  pin[2] = '\0';

  if (atoi(cmd) > 90) {
    strncpy(val, messageBuffer + 4, 2);
    val[2] = '\0';
    strncpy(aux, messageBuffer + 6, 3);
    aux[3] = '\0';
  } else {
    strncpy(val, messageBuffer + 4, 3);
    val[4] = '\0';
    strncpy(aux, messageBuffer + 7, 3);
    aux[4] = '\0';
  }

  if (debug) {
    Serial.println(messageBuffer);
  }
  int cmdid = atoi(cmd);

  // Serial.println(cmd);
  // Serial.println(pin);
  // Serial.println(val);
  // Serial.println(aux);

  switch(cmdid) {
    case 0:  sm(pin,val);              break;
    case 1:  dw(pin,val);              break;
    case 2:  dr(pin,val);              break;
    case 3:  aw(pin,val);              break;
    case 4:  ar(pin,val);              break;
    case 97: handlePing(pin,val,aux);  break;
    case 98: handleServo(pin,val,aux); break;
    case 99: toggleDebug(val);         break;
    default:                           break;
  }
}

/*
 * Toggle debug mode
 */
void toggleDebug(char *val) {
  if (atoi(val) == 0) {
    debug = false;
    Serial.println("goodbye");
  } else {
    debug = true;
    Serial.println("hello");
  }
}

/*
 * Set pin mode
 */
void sm(char *pin, char *val) {
  if (debug) Serial.println("sm");
  int p = getPin(pin);
  if(p == -1) { if(debug) Serial.println("badpin"); return; }
  if (atoi(val) == 0) {
    pinMode(p, OUTPUT);
  } else {
    pinMode(p, INPUT);
  }
}

/*
 * Digital write
 */
void dw(char *pin, char *val) {
  if (debug) Serial.println("dw");
  int p = getPin(pin);
  if(p == -1) { if(debug) Serial.println("badpin"); return; }
  pinMode(p, OUTPUT);
  if (atoi(val) == 0) {
    digitalWrite(p, LOW);
  } else {
    digitalWrite(p, HIGH);
  }
}

/*
 * Digital read
 */
void dr(char *pin, char *val) {
  if (debug) Serial.println("dr");
  int p = getPin(pin);
  if(p == -1) { if(debug) Serial.println("badpin"); return; }
  pinMode(p, INPUT);
  int oraw = digitalRead(p);
  char m[7];
  sprintf(m, "%02d::%02d", p,oraw);
  Serial.println(m);
}

/*
 * Analog read
 */
void ar(char *pin, char *val) {
  if(debug) Serial.println("ar");
  int p = getPin(pin);
  if(p == -1) { if(debug) Serial.println("badpin"); return; }
  pinMode(p, INPUT); // don't want to sw
  int rval = analogRead(p);
  char m[8];
  sprintf(m, "%s::%03d", pin, rval);
  Serial.println(m);
}

void aw(char *pin, char *val) {
  if(debug) Serial.println("aw");
  int p = getPin(pin);
  pinMode(p, OUTPUT);
  if(p == -1) { if(debug) Serial.println("badpin"); return; }
  analogWrite(p,atoi(val));
}

int getPin(char *pin) { //Converts to A0-A5, and returns -1 on error
  int ret = -1;
  if(pin[0] == 'A' || pin[0] == 'a') {
    switch(pin[1]) {
      case '0':  ret = A0; break;
      case '1':  ret = A1; break;
      case '2':  ret = A2; break;
      case '3':  ret = A3; break;
      case '4':  ret = A4; break;
      case '5':  ret = A5; break;
      default:             break;
    }
  } else {
    ret = atoi(pin);
    if(ret == 0 && (pin[0] != '0' || pin[1] != '0')) {
      ret = -1;
    }
  }
  return ret;
}

/*
 * Handle Ping commands
 * fire, read
 */
void handlePing(char *pin, char *val, char *aux) {
  if (debug) Serial.println("ss");
  int p = getPin(pin);

  if(p == -1) { if(debug) Serial.println("badpin"); return; }
  Serial.println("got signal");

  // 01(1) Fire and Read
  if (atoi(val) == 1) {
    char m[16];

    pinMode(p, OUTPUT);
    digitalWrite(p, LOW);
    delayMicroseconds(2);
    digitalWrite(p, HIGH);
    delayMicroseconds(5);
    digitalWrite(p, LOW);

    Serial.println("ping fired");

    pinMode(p, INPUT);
    sprintf(m, "%s::read::%08d", pin, pulseIn(p, HIGH));
    Serial.println(m);

    delay(50);
  }
}

/*
 * Handle Servo commands
 * attach, detach, write, read, writeMicroseconds, attached
 */
void handleServo(char *pin, char *val, char *aux) {
  if (debug) Serial.println("ss");
  int p = getPin(pin);
  if(p == -1) { if(debug) Serial.println("badpin"); return; }
  Serial.println("signal: servo");

  // 00(0) Detach
  if (atoi(val) == 0) {
    servo.detach();
    char m[12];
    sprintf(m, "%s::detached", pin);
    Serial.println(m);

  // 01(1) Attach
  } else if (atoi(val) == 1) {
    // servo.attach(p, 750, 2250);
    servo.attach(p);
    char m[12];
    sprintf(m, "%s::attached", pin);
    Serial.println(m);

  // 02(2) Write
  } else if (atoi(val) == 2) {
    Serial.println("writing to servo");
    Serial.println(atoi(aux));
    // Write to servo
    servo.write(atoi(aux));
    delay(15);

    // TODO: Experiment with microsecond pulses
    // digitalWrite(pin, HIGH);   // start the pulse
    // delayMicroseconds(pulseWidth);  // pulse width
    // digitalWrite(pin, LOW);    // stop the pulse

  // 03(3) Read
  } else if (atoi(val) == 3) {
    Serial.println("reading servo");
    int sval = servo.read();
    char m[13];
    sprintf(m, "%s::read::%03d", pin, sval);
    Serial.println(m);
  }
}

## Then, make AWESOME JavaScript

↓

## LED blinking var arduino = require('duino'), board = new arduino.Board(); var led = new arduino.Led({ board: board, pin: 13 }); led.blink();

no fs.XXXX

quite simple and elegant way

easy, huh?

BeagleBone + NodeJS

↓

First Steps

Buy SDCARD
Copy Pre-installed image into SDCARD
Power On
Open Browser

PRE-INSTALLED nodeJS

AND Cloud9 IDE

it's running now!

## OK, LED FIRST(AGAIN)

↓

## BoneScript require('bonescript'); ledPin = bone.P8_3; setup = function() { pinMode(ledPin, OUTPUT); }; loop = function() { digitalWrite(ledPin, HIGH); delay(1000); digitalWrite(ledPin, LOW); delay(1000); };

BoneScript

easy, huh?

Raspberry Pi + NodeJS

↓

First Steps

Buy SDCARD
Copy Pre-installed image into SDCARD
Power On
Install NodeJS
(And something more)

## rpi-gpio

[https://github.com/JamesBarwell/rpi-gpio.js](https://github.com/JamesBarwell/rpi-gpio.js)

## OK, LED FIRST(AND AGAIN)

↓

## rpi-gpio var gpio = require('rpi-gpio'); gpio.setup(17, gpio.DIR_OUT, write); function write() { gpio.write(17, true, function(err) { if (err) throw err; console.log('Written to pin'); }); }

easy, huh?

These hardware make you prototyping easily!

so...

DON'T BE AFRAID

TO BUY ONE

## Making Things Fun with nodeJS!

## Questions?

My Arduino RC Project!

BUY A CAR FIRST

RE-ASSEMBLE IT

Ooops..

TA;DA

## Which one is better?

Model B now ships with 512MB of RAM!

It's up to you

## Where can I buy these thing?

### These sites might help you! * [Arduino](http://arduino.cc/en/Main/Buy) * [Element14](http://element14.com) * [Adafruit](http://adafruit.com) * [ICBank](http://icbank.com)

# THANKS