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Michael
- 6th February 2010, 18:51
If I did a simple PIC RS232 infrared remote 8N1 just to represent 8 switches, will a universal remote (like a harmony) be able to learn the rs232?

Been a while since I built an ired device -- what is the carrier frequency that's popular -- isnt it 40khz or something?

Anyway, my goal is to put a simple power on/off on my PC and I would like it to be part of the harmony's "activity" routine.

I suppose I may have to go with one of the standard remote protocols rather than rs232 ?

Any tips on getting this project done? thanks

Bruce
- 6th February 2010, 18:59
I don't know anything about the Harmony remote, but 38kHz & 40kHz are the most popular
carriers.

If you want to try HSEROUT to send data modulated at 40kHz, I just posted an example in
this thread http://www.picbasic.co.uk/forum/showthread.php?t=12628 showing how to do
it with the new PIC16F1827 using the built-in Data Signal Modulator.

Michael
- 6th February 2010, 21:30
Bruce --

Do you think the Harmony (or any universal for that matter) will read RS232
as a valid signal?

Ever tried it?

Don't know if they expect the data to be in one of those remote formats and won't accept what it doesn't like?

Michael
- 6th February 2010, 21:30
what I mean is the "learning" function on these remotes.

Bruce
- 6th February 2010, 21:34
Hi Michael,

I've never tried a learning remote with serial IR data before, but I would be interested
in knowing if it worked or not. Could make for some really interesting projects.

Just don't have a learning remote to test.

Dave
- 7th February 2010, 00:15
Bruce,and Michael, You can use any Pic micro with a pwm output to generate modulated serial data. I have been doing it for about 2 years since I started using 16F88's for remote controls. All you need are 2 diodes with there anodes connected 1 to the tx output and 1 to the pwm output and the cathodes driving a pnp transistor for the IR drive... Try it...

Dave Purola,
N8NTA

Bruce
- 7th February 2010, 00:41
Hi Dave,

Thanks. I've done a lot of IR apps with/without external components. Except for the IR LED
and resistor of course.

I just worked up the Data Signal Modulator example while playing with the new 16F1827.

The DSM module on this thing goes well beyond simple modulated IR communications. And
a single resistor + IR LED is all you need to setup an IR wireless network with multiple PICs
all using the hardware USART with HSERIN/HSEROUT.

dhouston
- 7th February 2010, 01:59
Learning remotes do no decoding but merely record an image of the signal for playback. The source of the learned signal should not matter.

Michael
- 7th February 2010, 17:55
Cool -- that's what I needed to know.

And your right Bruce, that could make for some (very) interesting ideas.

Be fun to even add a PIC Ired rcvr to the serial port and maybe write some VBnet stuff.

For now though, just on/off control of my media PC with the Harmony.