IR is a pretty wide subject, although it’s probably the easiest to play with as you’ve probably got all the bits lying around your home already.
The first thing to do is to determine what IR transmitter (handset) you’re going to use. Press the + or - VOL button, and see what you get. Unless you're going to build your own IR handset transmitter, this is really the starting point.
I’ve appended a jpeg of the signal from a typical TV remote with the – VOL button pressed so you can see what you're going to deal with. You get a repeating burst of pulses across a set time period - in this case 25mS - which unfortunately is quite different for each manufacturer and function.
There are lots of ways of decoding IR… quite simply you just have to read-in the pulses and determine if they’re long or short… Have a look at microchips application note AN657 for some clues.
http://www.microchip.com/download/ap...6c5x/00657.pdf
Melanie
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