Need Help with Infrared recievers/transmitters

zo0o0om

Hey I am trying to make a TV remote from scratch, So far I have managed to build a receiver using a solar panel hooked up to my computer microphone jack, and audacity to record the infrared light that it emits.

My problem is that I am not sure how to decode the infrared light so that I can output the same signals using pbasic and a basic stamp 2 chip with a IR LED, i've read a bunch of guides and they tell me to measure the length that the IR LED signal 'bursts', but what do you do with those numbers?

Any help is appreciated,
Thank you!

zo0o0om

There is the input from the IR receiver, 90.884ms OFF, 23.401ms ON.

Mike Green

There's a Parallax tutorial called "IR Remote for the BoeBot robot" that explains how IR remotes work and how to receive and decode IR remote signals. There's also some stuff in there on generating IR remote signals.

Look at the main Parallax webpage and click on Downloads. You'll see a button for "Educational Tutorials & Translations". You'll find this tutorial there.

erco

Also see·Parallax' Weekend App Kit on IR signals at
http://www.jameco.com/Jameco/Products/ProdDS/282933APP.pdf

You'll need to add a simple·external oscillator to generate your 38-40 kHz IR carrier signal, and your stamp can modulate that. Check this thread, I sent a Sony code (power=21) a few posts down the page: http://forums.parallax.com/showthread.php?p=759751


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·"If you build it, they will come."

Post Edited (erco) : 7/26/2010 10:19:44 PM GMT

APSpijkerman

I have done something like that years ago with BS2 and javelin stamp.

I think i have the javelin code on this machine, hmm yub.

I took a IR receiver module, (which demodulates the IR) and hooked it up to a stamp.

Then i made a loop that reads the lengths of pulses to the memory of the javelin stamp:

do {
action = CPU.readPin(CPU.pins[noparse][[/noparse]7]);
} while(action == false);


do {
//code = CPU.pulseIn(32767, CPU.pin7, true);
r = CPU.rcTime(32767, CPU.pin7, false); // false
a[noparse][[/noparse]len] = r;// + 20;
len++;
//code = CPU.pulseIn(32767, CPU.pin7, false);
r = CPU.rcTime(32767, CPU.pin7, true); // true
a[noparse][[/noparse]len] = r;// + 5; // correction for loop
len++;
} while (r > 2 && len < 98);


Then copied the data from the memory to the EEPROM.
And for playing i did it in reverse.
I used a 10Mhz oscillator, divided that frequency by 256 by a 4040 counter .. then put that signal
of 39khz through an AND port together with the signal from a pin from the basic stamp to
an IR led.

If an IR code needs to be send it reads it from EEPROM to ram, and from there it
is send with something like this:

for (t = 0; t < len; t+=2){
CPU.writePin(CPU.pins[noparse][[/noparse]0], true);
CPU.delay( a[noparse][[/noparse]t] );
CPU.writePin(CPU.pins[noparse][[/noparse]0], false);
CPU.delay( a[noparse][[/noparse]t+1]);
}


greetings Arend-Paul Spijkerman

Basic stamp scope

zo0o0om

PERFECT!! Thank you guys!

japcy07lol

Hey/I am new in this forum I encounter having infrared but I havent yet experience conflict.What was your worst experience regarding infrared?Let me know!!
Regards!

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gw2 gold

APSpijkerman

I have tried making a infrared "Universal remote" using a Javelin stamp
and a basic stamp.

I works great on the javelin stamp, but it looks like the basic stamp
isnt fast enough to capture the smallest pulses.

Anyway .. i used the stampdock software as the "controls" of the
remote, and to draw a graph of the pulses it receives and sends.
Also it is able to store and load the IR codes on the harddisk of the PC.

You might find it usefull while experimenting with infrared.
You can find the software here: http://apsdev.com/stampremote/home.html
Note that it says Javelin, but the basic stamp version is also in the archive.