Tom Metro wrote: > stuart wrote: >> ...an IR transmitter is usually not much more than an inferred LED >> and a resistor. > > True, providing the carrier frequency and modulation are both being > generated in software. That approach will give you the widest range of > compatibility, providing your software can keep up, but also the highest > CPU load.
Yeah, but it only last for a few seconds and usually happens during event changes. We've been over that here on this list (that and having the mvpmc become an IR blaster its self). > If you know the carrier frequency your device uses (typically 40 to 80 > KHz), you might be better off finding a commercial IR blaster that > included the appropriate hardware to generate that, so the computer only > need to supply the data signal to modulate the carrier. I'm guessing, but I'd say a blaster operating about 40KHz would cover just about everything. The parts to make such a thing are trivial and can be housed in a 9 pin serial connector. Humm, but I can't find what I'm thinking of (using a 74CH00 chip, half as a monostable multi vibrator operating at 40KHz and the other half to help gate the signal). Instead I found things like: > http://www.lirc.org/improved_transmitter.html ...which need each pulse controlled as you said above. On the outside chance what you want to control is an older Sony device with an s-link input you can skip the modulation part. All s-link is is the remote codes w/o the ~40KHz carrier. That plus a really long pulse signalling an upstream device is powering up. > Your best bet at figuring out what is going on is to get an IR > phototransistor and hook it up to an oscilloscope (that you can perhaps > borrow from a friend). Then compare the signal from the original remote > to the one produced by the IR blaster. > > -Tom I've not used this one (IR receiver), but have used some of TommyTiler's other devices. If it works as good as his UBS programmers, this would be waaaaayyyyyy better then an O-Scope: > http://www.hifi-remote.com/forums/viewtopic.php?t=9405 Search for "Infrared Signal Recorder". But before I do that, I'd search the hifi-remote.com web site. Chances are very good that someone has already captured the codes you are interested in and published them here. ...ahhh, hardware. ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Mvpmc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/mvpmc-users mvpmc wiki: http://mvpmc.wikispaces.com/
