/*
Apple IR reader for Duemilanove v1
 
Released under the Creative Commons Attribution Non-Commercial Use License
http://creativecommons.org/licenses/by-nc/3.0/
*/
/*
Arduino connections
D7 Connected via a 220 ohm resistor to the IR sensor
D13 Connected to the IR LED 
*/
int IR_sensor = 7;
int IR_LED = 13;
int NumBits = 32; // Number of bits received
int Bit_0 = 510; // Signal length in us
int Bit_1 = 1630; // Signal length in us
long Bit_delay = 570; // Down time for 1 and 0
int Bit_start = 8000; // Minimal signal length of the start signal in us 
int Bit_error = 100; // Pulse width allowed = e.g. Bit_0 +/- Bit_error
int result = 0; // Stores the decimal value of the code that was received
int Showcode = 0; // If 1: print the received code to the serial port
int Wait_time = 200; // Waiting time before the codes starts to read the next signal
int interval = 1000; // Interval (milliseconds) at which two clicks are accepted as double click
int menu_n_click = 0; // Stores how many times the button is used within "interval"
long menu_previous = 0; // Stores the last time this button was used
int voldown[32] = {0,1,1,1,0,1,1,1,1,1,1,0,0,0,0,1,0,0,1,1,0,0,0,0,1,0,0,0,0,1,0,1}; // Code for the volume down button
long time_up = 5;
long time_down = 12;
void setup()
{
pinMode (IR_sensor, INPUT);
pinMode (IR_LED, OUTPUT);
 
Serial.begin(9600); // Start receiving Serial Data
Serial.println("Serial reading started"); // Just to check if the communication is ok
}
 
// Main Program Loop
void loop()
{
do
{
if ((millis() - menu_previous > interval) && (menu_n_click > 0)) // No more clicks so time to start the action -> this is realized "interval" us after the last time this button was used
{
if (menu_n_click > 2)
{
menu_n_click = 0;
Serial.println("# of times is reset"); // Just for testing
}
else
{
switch (menu_n_click)
{
case 1:// Menu
Serial.println("Menu");
menu_n_click = 0;
break;
case 2: // 
Showcode = 1 - Showcode;
menu_n_click = 0;
if (Showcode == 1)
{
Serial.println("Codes will be displayed");
}
else
{
Serial.println();
Serial.println("Codes will not be displayed");
}
}
}
}
}
while ((pulseIn(IR_sensor,LOW) < Bit_start));
 
Read_signal();
delay(100);
Do_action();
delay(Wait_time);
 
}
void Read_signal() // Reading and processing the IR signal
{
// We start to read the signal length of each pulse
int pulse[NumBits]; // Here we store the signal length in us
for (int i = 0; i < NumBits; i++)
{
pulse[i] = pulseIn(IR_sensor,HIGH);
}
if (Showcode == 1)
{
Serial.println();
Serial.print("Signal pulse length in micro second: ");
for (int i = 0; i < NumBits; i++)
{
Serial.print(pulse[i]);
Serial.print(" ");
}
Serial.println();
}
 
// We convert the signals length to bits (0, 1 or invalid)
int bit[NumBits]; // Here we store the bit 
for (int i = 0; i < NumBits; i++)
{
if ((pulse[i] > Bit_1 - Bit_error) && (pulse[i] < Bit_1 + Bit_error)) // Is it a 1?
{
bit[i] = 1;
} 
else if ((pulse[i] > Bit_0 - Bit_error) && (pulse[i] < Bit_0 + Bit_error)) // Is it a 0?
{
bit[i] = 0;
} 
else //data is invalid...
{
Serial.print("Signal length (");
Serial.print(pulse[i]);
Serial.println(") is outside the range.");
}
}
 
if (Showcode == 1)
{
Serial.print("Pulses converted to binary code: ");
for (int i = 0; i < NumBits; i++)
{
Serial.print(bit[i]);
}
Serial.println();
}
 
// We convert the bits to a decimal value
int seed = 1;
result = 0;
for (int i = (0+16) ; i < (NumBits-8) ; i++) 
{ 
if (bit[i] == 1) 
{
result += seed;
}
seed *= 2;
}
if (Showcode == 1)
{
Serial.print("Binary code converted to integer: ");
Serial.println(result);
}
}
void Do_action() // Do something with the read data
{
// We do the action if the right key was pressed
switch (result)
{
case 6: // Next song
Serial.println("Next song");
break; 
case 9: // channel down button
Serial.println("Previous song");
break;
case 10: // Volume up
Serial.println("Volume up");
signal_send(); // Here we send the IR signal for the button selected in this function
break;
case 12: // Volume down
Serial.println("Volume down");
break;
case 5: // Play/pause
Serial.println("Play/pause");
break;
case 3: // Menu
if (millis() - menu_previous < interval) // It is a multiple click
{
menu_previous = millis(); // Time since the last click is set to this click
menu_n_click += 1;
}
else // It's a first click
{
menu_previous = millis(); // Time since the last click is set to this click
menu_n_click = 1;
}
break;
default:
Serial.println("Key is not programmed");
break;
}
}
//function which send the command over an IR-led
void signal_send()
{
if (Showcode == 1)
{
Serial.println("sending...");
}
for (int i = 0; i < 365; i++) //start the message with a 9.1 ms time up
{
Send_IR();
}
delayMicroseconds(4500);
for (int b = 0; b < 32; b++)
{
for (int i = 0; i < 25; i++) // 1 & 0 start with 530 us high
{
Send_IR();
}
if (voldown[b] == 1) // This is the array of the code that will be used, in this case the volume down code
{
delayMicroseconds(1640); // Signal low for a 1 is 1650 us
}
else
{
delayMicroseconds(610); // Signal low for a 1 is 530 us
}
}
for (int i = 0; i < 25; i++) // End signal 530 us high
{
Send_IR();
}
delay(25);
}
// Here we do the modulation of the IR signal
void Send_IR()
{
digitalWrite(IR_LED, HIGH);
delayMicroseconds(time_up);
digitalWrite(IR_LED, LOW);
delayMicroseconds(time_down);
}