Re: Ability to drive multiple IR transmitters independantly from PC

[nobody@xxxxxxxxxxxx (Dave Houston)]

Alexis <snoopy@xxxxxxxxxxxxxxxxxxxxx> wrote:

>Dave Houston wrote:
>> Since you were talking about USB repeaters I assumed cost was not a factor.
>
>Cost is always a factor! ;)
>
>To be honest, I hadn't really considered the cost of USB repeaters as
>extending the IR LED wiring was always my first plan - my soldering
>skills, while not fantastic, are more than up to the challenge of that.
>  Anything involving breadboard and through-hole components I can
>usually manage, as an indication of my capabilities - but I don't have
>the kit to do surface-mount soldering.
>
>For the record, I'm not at all adverse to paying for a commercial
>solution, but it needs to not be *too* expensive.  Say a maximum cost in
>the region of $500-$750 for 10 displays - ideally less, of course!
>
>> What are the details on the codes you need to send? Carrier frequency, code?
>> It may be possible to design something quite cheap to accomplish this. Can
>> you program in Basic?
>
>I have to admit to my ignorance on this unfortunately.  The projectors
>are NEC VT650 models, but unfortunately I'm unable to find any details
>of the IR specifications on the 'net.  Is there anything you can suggest
>without knowing this information?
>
>Java is my programming language of choice - I've done projects that
>interface with parallel and serial ports from within Java, so if you
>have something like that in mind, I should be able to build the code to
>drive it without too much difficulty.  I also have plenty of friends who
>can code in C/C++, and I'm sure some of them will have Basic skills, so
>I'll figure something out on the software side if you can give me some
>hints on the hardware side!

This woould be fairly simple to do in ZBasic (free) running on a ZX-40 (30
pins could be used to control 30 projectors) which costs $30. You need a
transistor and a few resistors in each circuit. You can buy surplus emitters
with long cords and wire as needed to extend them. Total is probably under
$100 built on vector board.

     http://www.zbasic.net

http://www.AllElectronics.com usually has surplus stick-on emitters. See
CAT# IR-21.

If you cannot find the codes on RemoteCentral it's a simple matter to
capture them with a sound card. See...

     http://davehouston.net/learn.htm

Or you could capture them with a TSOP1100 and the ZX-40.

Anand can point you to another site that has an alternate method of
capturing the codes.

If all else fails, buy one USB-UIRT to capture the codes and carrier
frequency.

Since you used meters when referring to the cable length I guess you're not
in the USA. You can probably find similar emitters elsewhere.

http://davehouston.net
http://tech.groups.yahoo.com/group/roZetta/
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