• Supporting 3 main IR protocols
• Able to learn one code and then react to this code - turn on the computer
• You can use crystal with any frequency you would like - no fixed timing
• Codes are send over UART so you can process the remote codes on PC for example in EventGhost
• Developed for ATmega8, easily portable to other ATmega & ATtiny
  

Protocols
Software decoder supports all protocols at once. Based on the length of the first pulse the software decides which protocol should use to parse the input signal.

[DONE] Philips RC5
http://wiki.altium.com/display/ADOH/Philips+RC5+Infrared+Transmission+Protocol
You need 36kHz infrared receiver & decoder

[DONE] Sony SIRC
http://picprojects.org.uk/projects/sirc/
Repeatable button presses are processed with some delay.
You need 40kHz infrared receiver & decoder

Hardware
Developed on ATmega8, possible to port to any ATmega/ATtiny with stack pointer and 16bit timer.

IR sensor & demodulator

• NEC: TSOP2238, SFH-5110-38 (38kHz)
• RC5 : TSOP2236, SFH-5110-36 (36kHz)
• SIRP: 40kHz

I hate if I have to correct timings in someone's project just because I have different crystal frequency.
Now you can use any crystal from range about 1MHz to 20Mhz!
Only if you need accurate UART baudrates, you'll have to use crystal with "magical" frequencies like 11,0592MHz etc.

IR sensor pin to PD2
Learn IR code jumper PB0
Computer switch contact to PB1

Debug LED - connect anywhere on PORTC.

Software
The received code is send over TX (PD1) pin with speed 115200 baud. The text format is "0x12EF\n\l".
For NEC: The first byte (higher 8 bits) is remote control address and the second byte (lower 8bits) is key code.

The code is I hope clear enough and self-explainable.
The pulses are measured with free running 16bit Timer1. There's no interrupts or Input Capture.

✓ - timing is reliable enough

Crystal	Timer	NEC	RC5	SIRC
7.3728MHz	8b	✓	✓	✓
	16b	✓	✓	✓
8MHz	8b
	16b
11.0592MHz	8b	✓	✓	✓
	16b	✓	✓	✓
14.318000
16MHz	8b
	16b

History

• 1.0 - Initial version
• 1.1 - Optional support for 8bit Timer0, so you can use Timer1 and Timer2 for 3 PWM on ATmega8
• 1.2 - Better synchronization of bits in RC5 protocol. Added bit error check for NEC & RC5 so they are perfectly reliable.