DIYbanter - View Single Post - Towards the goal of a truly universal IR remote control

Paul Hovnanian P.E.

wrote:

[snip]

The problem is the large variety of codes and carrier frequencies
available. There isn't enough room to to store all the variants in a
low power system. I believe the Logitech Harmony is programmed via the
PC so only needs a small amount of memory. I know they're expensive -
that's why I don't have one but many folks swear by them (and a few
swear at them).

The Logitech unit has some interesting features. Like a graphical interface
and the ability to 'macro script' certain functions like turning on the
monitor, set top box and sound system with one button press.

But for a basic remote, I've used something like the Sony RM-VZ220
(available at Radio Shack for $12-$14). They have hundreds of preprogramed
device codes built in. And some oddball equipment can be partially
controlled if you can find the same make and a similar model.

That might get you to a complete solution. If you can get a remote that
operates some of the appliance functions, you can throw a 'scope on the
output and reverse engineer those that work. Once you know the packet
format (preamble, length, checksums, etc.) you might be able to 'fill in
the blanks' by firing some unsupported codes in the same format and see
what happens.

--
Paul Hovnanian
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