Sujet : Re: Ir remotes
De : alien (at) *nospam* comet.invalid (Jan Panteltje)
Groupes : sci.electronics.designDate : 20. May 2024, 14:37:41
Autres entêtes
Message-ID : <v2fg6m$hq8c$1@solani.org>
References : 1 2 3
User-Agent : NewsFleX-1.5.7.5 (Linux-5.15.32-v7l+)
On a sunny day (Mon, 20 May 2024 11:50:22 +0200) it happened Lasse Langwadt
<
llc@fonz.dk> wrote in <
v2f6cv$3tvoi$1@dont-email.me>:
On 5/20/24 09:15, Don Y wrote:
On 5/20/2024 12:01 AM, Don Y wrote:
My understanding is that Ir remotes modulate an Ir "carrier" signal
in a particular pattern to express a particular "code" corresponding to
the key pressed/held.
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And, that different "chipsets" use different carriers and encodings.
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Is there a front-end that is tuned to the particular carrier
in the receiver? Or, is all of this done "digitally"?
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I.e., with a fast-enough (Ir) photodetector, should I be able to
decode ANY signal from ANY "remote"?
And, before anyone mentions the obvious, I've already looked at lircd
which is the reason behind this post; why do they claim they can handle
ALMOST all remotes? Is this a limitation of their hardware implementation?
Or, timing problems in the way they try to process the raw video signal?
>
afaik almost all use a 30-50kHz carrier, nominally something like 38kHz,
I think the common IR receivers have build in bandpass filter, so it is
just a matter of interpreting bits (there's a few common protocols)
>
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I know that B&O (used to?) be an exception with a 455kHz carrier, I'm
guessing because someone clever many decades ago thought to use an AM IF
filter
https://panteltje.nl/panteltje/pic/ir_pic/ used it to control my cable modem.
But I also have a Chungop SRM403E remote that can learn codes from other remotes.
In fact many remotes can learn codes from other remotes,
I have an other Chinese one that can.
Makes life sometimes easier, now you only need one remote for say 3 different devices.