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Radiance
- 4th August 2003, 14:23
Does anyone have any experience with PICS and remote control projects? I'm trying to decide the best way to add a remote volume control to an amplifier, and need a VERY minimal implementation of a remote to send an up and down signal to a digital volume control (a dallas ds1802). RF or infrared will both do, with IR being the preferable (but more difficult probably) choice.

Nik

Ingvar
- 6th August 2003, 13:26
Hi Nik,

I've done a couple of infrared remotecontrols, both transmitter and reciever. It's not too difficult.

/Ingvar

Melanie
- 6th August 2003, 16:13
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.

www.microchip.com/download/appnote/devspec/16c5x/00657.pdf

Melanie