Custom IR signals?

I have a quick question. Would it be possible to create an app or add via firmware the ability to create a custom ir signal? For example if you need the ir to send out a strobe of 10 flashes .05 seconds apart at 11hz? I am working on a project that would be greatly improved if I can add the ability to control various functions via. IR.


If you look at the schematic, the output LEDs are hooked directly to the micro, not a mystery dedicated “transceiver” chip, aside from the TSOP for input.

So that means, for output (again AFAIK, unless I missed something important this was quick research) the chip ‘simply’ is a. creating a 38Khz carrier wave and then b. pulsing that wave on the order of milliseconds.

How it’s done is in the firmware source somewhere. I’ve done it in AVR-land before, similarly. Sometimes the 38Khz part is done by setting a hardware PWM, and then turning that on and off in the ms pulses for the encoding. Getting a good timer is usually key to timing ms accurately, spin loops can be finicky and unreliable (particularly in a multi-tasking OS such as this). Sorry I don’t have more specifics, I haven’t tracked down the exact answer to “how it’s done in the firmware” just yet myself.

Beyond that creating your own custom IR protocol isn’t horrible work - if you grab a TSOP…381 I think ( , they’re relatively inexpensive) you can test that things are working on a receiving 38Khz end.

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