NEC 80 protocol remote transmitter

[emdee]

nec protocol avr

Hi,
I decoded the NEC80 remote system and I have the C-code in codevision version.
I had a lot of help from code from YAMPP project by Jesper Hansen.
W*W.YAMPP.COM

So I have the code for decoding a Nec-80 remote ( like Kenwood's)
Now I like to make a transmitter also. I want to use an ATMEL AVR uC for this.
Anyone done this?
I have no idea on how exact the generated carrier wave has to be..does it has to be Sinus to be perfect, or can I use Block signal?
Anyone?

 

[ajit4u]

Re: nec protocol avr

show me the code , so i can help

 

[betwixt]

The carrier waveform is not important, usually an LED is hard switched from off to as much current as the remote can pump through it. The IR LEDs are designed for high current pulse operation rather than continuous.
I suggest you use 38KHz as the carrier frequency and switch it on/off under software control. You might be able to produce the carrier in software or use a PWM output or even something like a 555 timer.

Brian.