Category Archives: home projects

1st code

As I moved all my electronic equipment in a cabinet, I had to foresee an IR extender. I first looked at commercial devices or ones that are based on a 555 timer, but wanted to keep the amount of components at a minimum. Hence, Arduino to the rescue:

This project is currently running on a full Arduino, but I’m going to port it to a barebone soon. Right now, it is capturing IR via a TSOP alike IR receiver connected to pin 2. As these signals are demodulated, I had to regenerate the 36kHz carrier via timer 2 and turn it on/off depending on the the captured signal. This seems to work fine for most of my devices, except for the Belgacom setup box, which reacts very slow for the moment.


  • try to combine this code with the IRremote library, so I can remotely control a led strip.
  • debug the Belgacom setup box issues
  • mount everything in a permanent enclosure
  • add an enc28j60 interface for future domotica enhancements

const byte LED = 10;  // Timer 2 “A” output: OC2A
int sensePin = 2;        // This is the INT0 Pin of the ATMega328
int sensePinInt = 0; // INT0 zit op pin 2, INT1 op pin 3

volatile int value = 0;  // Sense value

void setup() {
pinMode (LED, OUTPUT);
pinMode(sensePin, INPUT);   // read from the sense pin
attachInterrupt(sensePinInt, state, CHANGE);

// set up Timer 2
TCCR2A = _BV (COM2A0) | _BV(WGM21);  // CTC, toggle OC2A on Compare Match
TCCR2B = _BV (CS20);   // No prescaler
OCR2A = 220; // 36khz
//  OCR2A =  209;          // compare A register value (210 * clock speed)
//  = 13.125 nS , so frequency is 1 / (2 * 13.125) = 38095
}  // end of setup

void loop() { }

void state() {
value = digitalRead(sensePin);

if (value)
TCCR2A &= !(_BV(COM2A0) | COM2A1); // PWM off
TCCR2A = _BV (COM2A0) | _BV(WGM21);  // PWM on