The Arduino Doorbell - Part 2 Software!

Firstly, here is the final Arduino code that I am using, its as best to perfect as I can get at present with only one real hiccup.

int ledPin = 13; // LED connected to digital pin 13

int potPin = 0; // white doorbell wire to analog pin 0

int val = 0;

long time = 0;

long debounce = 1000;

void setup() {

pinMode(ledPin, OUTPUT); // sets the digital pin as output

Serial.begin(9600); // open serial port at 9600 baud

digitalWrite(14 + potPin, HIGH); // set pullup on the analog pin

// (analog 0 = digital 14, a1 = d15, etc)

}

void loop() {

val = analogRead(potPin);

if (val < 200) { // if the circuit is completed

// (for me, it generally drops from 1023 to ~ 15 when 'ringing')

if (millis()-time > debounce) {

Serial.println("ON");

digitalWrite(ledPin, HIGH); // sets the LED on

delay(1000); // ...wait for 2 seconds

digitalWrite(ledPin, LOW); // and turns the LED off

time = millis();

}

}

}

I cannot take credit for this code please see this post http://rooreynolds.com/2008/05/14/hacking-the-doorbell/ for the original code, I have just modified aspects to suit my needs.

What this will do is when the button is pushed, it will light the test LED and send the "ON" text via the arduino to your pc's com port.

Now the hardest part! I have yet to find anyone who has done this hardware setup with a windows machine and wanting to use growl/prowl, the closest I could find was this post http://www.grantgibson.co.uk/blog/index.php/2009/03/29/putting-doorbell-online/as this guy is using a windows machine but is using a web function as a notification.

So now I have a base to use in ActivePerl as my listen and trigger code, now I wanted to run the command C:\Program Files\Growl for Windows\Growlnotify "There is someone at the door" as a dos command instead of the 'http://your action here' command.

Here is my Perl code:

use Win32::SerialPort;

use LWP::Simple;

my $port = Win32::SerialPort->new ("COM3");

$port->databits(8);

$port->baudrate(19200);

$port->parity("none");

$port->stopbits(1);

my $count = 0;

while (1) {

my $char = $port->lookfor();

if ($char) {

$char = substr $char, 0, 2;

print " Doorbell status: " . $char . " \n";

if ($char eq "ON") {

print "Doorbell is on \n";

system 'C:\growlnotify "There is someone at the Door"';

}

}

sleep(1);

}

Note: I have removed the bottom part of Grant's code as it wasnt needed for this application, then I changed the http line, to the system command, however this is the first time consuming problem, the command will not run from a folder that has a space in the name i.e Program Files therefore I had to copy the growlnotify.exe to the root directory and run it directly from C:\.

The text following the growlnotify command can be changed to anything you wish.

Note 2: Dont try and run the perl code with the arduino software open, as you will get an error as the com port is in use by the arduino software.

Note 3: Perl when installed doesnt tell you this but you need to reboot the machine in order to set the path variable to enable perl to run directly from any command line, test by using the command c:\perl -v this should return details about the perl version, if it doesnt you will need to do some troubleshooting.

Then all that needs doing is to set up growl and prowl, this will involve buying the prowl app, setting an API key, and modifing your growl settings all of which are fairly easy and there is plenty of info on the web.

That should be about it, set your hardware up, flash with code, set up perl, run perl doorbell.pl from your command line and push the button!

http://youtu.be/gaipAeS--LQ