IR question...
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Posts: 46,084
In a message dated 5/9/2004 6:32:46 PM Eastern Daylight Time, bjm1287@r...
writes:
> Hi all. I'm trying to find some documentation on transmitting IR
> signals from a BS2. What I'm trying to accomplish is turning on a TV
> via IR when the stamp first turns on. I can find tons of information
> on recieving IR data, but no examples of transmitting IR. Any help
> would be greatful.
>
If you are trying to turn on a television set, then you have to determine
what IR protocol is it using - Sony, Phillips, etc., then duplicate that signal.
IR signals that control TVs are not frequency-dependent, but time (pulse
width)
dependent. It would be necessary to look at the format of the necessary
commands, then duplicate them. You are embarking on a very tough project.
Sid Weaver
New item - New prices.........
http://www.visualmuses.com/chipcircuit/index.html
[noparse][[/noparse]Non-text portions of this message have been removed]
writes:
> Hi all. I'm trying to find some documentation on transmitting IR
> signals from a BS2. What I'm trying to accomplish is turning on a TV
> via IR when the stamp first turns on. I can find tons of information
> on recieving IR data, but no examples of transmitting IR. Any help
> would be greatful.
>
If you are trying to turn on a television set, then you have to determine
what IR protocol is it using - Sony, Phillips, etc., then duplicate that signal.
IR signals that control TVs are not frequency-dependent, but time (pulse
width)
dependent. It would be necessary to look at the format of the necessary
commands, then duplicate them. You are embarking on a very tough project.
Sid Weaver
New item - New prices.........
http://www.visualmuses.com/chipcircuit/index.html
[noparse][[/noparse]Non-text portions of this message have been removed]
Comments
signals from a BS2. What I'm trying to accomplish is turning on a TV
via IR when the stamp first turns on. I can find tons of information
on recieving IR data, but no examples of transmitting IR. Any help
would be greatful.
Thanks,
--Brian
Not as elegant as some may wish but....
Why not hack the remote that goes to that particular TV? All that would be
necessary would be a small relay or perhaps a transistor across the "on"
button of the remote.
Then when the stamp powers on have it execute a simple "hi" or "low"
(depending on wheter you've wired your transistor or relay for active hi or
lo)
I know it's not very elegant. But even I could make that happen.
Rus
(Still learning a lot you this group, and very thankful for all help in the
past)
Original Message
From: Newzed@a... [noparse]/noparse]mailto:[url=http://forums.parallaxinc.com/group/basicstamps/post?postID=Shv458nGUccLwExwzNxKSSEole0AsA7YOmNIOok-4jN4oKX_OGq2bXJDmsnuEySjmkGLSyh30fJx]Newzed@a...[/url
Sent: Sunday, May 09, 2004 5:43 PM
To: basicstamps@yahoogroups.com
Subject: Re: [noparse][[/noparse]basicstamps] IR question...
In a message dated 5/9/2004 6:32:46 PM Eastern Daylight Time,
bjm1287@r...
writes:
> Hi all. I'm trying to find some documentation on transmitting IR
> signals from a BS2. What I'm trying to accomplish is turning on a TV
> via IR when the stamp first turns on. I can find tons of information
> on recieving IR data, but no examples of transmitting IR. Any help
> would be greatful.
>
If you are trying to turn on a television set, then you have to determine
what IR protocol is it using - Sony, Phillips, etc., then duplicate that
signal.
IR signals that control TVs are not frequency-dependent, but time (pulse
width)
dependent. It would be necessary to look at the format of the necessary
commands, then duplicate them. You are embarking on a very tough project.
Sid Weaver
New item - New prices.........
http://www.visualmuses.com/chipcircuit/index.html
[noparse][[/noparse]Non-text portions of this message have been removed]
To UNSUBSCRIBE, just send mail to:
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Body of the message will be ignored.
Yahoo! Groups Links
of home audio/video electronics. Some are
fairly easy, like the Sony protocol. Some
are much harder.
Basically, you want to output a 38 Khz signal
'pulse'. The duration of the 'pulse' and the
duration of silence between pulses make up the
protocol your TV or VCR understands.
The easiest way to go about this is to buy a
remote, set it for your television, then record
the protocol is uses, then program that protocol
into the BS2.
It is doable, but not trivial. Search google for
IR Sony Protocol, and IR Phillips RC-5 protocol.
There are some very good web-sites out there with
more info.
--- In basicstamps@yahoogroups.com, "Brian M." <bjm1287@r...> wrote:
> Hi all. I'm trying to find some documentation on transmitting IR
> signals from a BS2. What I'm trying to accomplish is turning on a
TV
> via IR when the stamp first turns on. I can find tons of
information
> on recieving IR data, but no examples of transmitting IR. Any help
> would be greatful.
>
> Thanks,
> --Brian
It's actually pretty easy to do this. The main problem is that the Stamp
doesn't have any independent PWM. Therefore, you need to generate the PWM,
uusally around 38kHz, in another way. You can do it with a 555 timer, or a
variety of other ways. Once you have the PWM going, all you need is a
Schmitt NAND gate like a 74HC132. You send a PWM signal to one side of the
NAND and the serial data on the other side. As to the particulars of the
protocol, it depends on the brand of device you are targeting.
HTH,
Jonathan
www.madlabs.info
Original Message
From: "Brian M." <bjm1287@r...>
To: <basicstamps@yahoogroups.com>
Sent: Sunday, May 09, 2004 2:31 PM
Subject: [noparse][[/noparse]basicstamps] IR question...
> Hi all. I'm trying to find some documentation on transmitting IR
> signals from a BS2. What I'm trying to accomplish is turning on a TV
> via IR when the stamp first turns on. I can find tons of information
> on recieving IR data, but no examples of transmitting IR. Any help
> would be greatful.
>
> Thanks,
> --Brian
>
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>
>
something like that, just taking the IR diode off the PCB in the
remote, mounting it in front of the TV, running wire to it from the
remote, and using a relay to just trigger the remote button....I was
trying to avoid that if possible, but it sounds like it's not easily
done...at least with my current skills and time frame.
Thanks all,
--Brian
--- In basicstamps@yahoogroups.com, "Rus Hardy" <rushardy@m...> wrote:
> Here's an idea to make the "very tough" easier.
>
> Not as elegant as some may wish but....
>
> Why not hack the remote that goes to that particular TV? All that
would be
> necessary would be a small relay or perhaps a transistor across the "on"
> button of the remote.
>
> Then when the stamp powers on have it execute a simple "hi" or "low"
> (depending on wheter you've wired your transistor or relay for
active hi or
> lo)
>
> I know it's not very elegant. But even I could make that happen.
>
> Rus
> (Still learning a lot you this group, and very thankful for all help
in the
> past)
>
>
Original Message
> From: Newzed@a... [noparse][[/noparse]mailto:Newzed@a...]
> Sent: Sunday, May 09, 2004 5:43 PM
> To: basicstamps@yahoogroups.com
> Subject: Re: [noparse][[/noparse]basicstamps] IR question...
>
>
> In a message dated 5/9/2004 6:32:46 PM Eastern Daylight Time,
> bjm1287@r...
> writes:
>
>
> > Hi all. I'm trying to find some documentation on transmitting IR
> > signals from a BS2. What I'm trying to accomplish is turning on a TV
> > via IR when the stamp first turns on. I can find tons of information
> > on recieving IR data, but no examples of transmitting IR. Any help
> > would be greatful.
> >
>
> If you are trying to turn on a television set, then you have to
determine
> what IR protocol is it using - Sony, Phillips, etc., then duplicate that
> signal.
> IR signals that control TVs are not frequency-dependent, but time
(pulse
> width)
> dependent. It would be necessary to look at the format of the
necessary
> commands, then duplicate them. You are embarking on a very tough
project.
>
>
> Sid Weaver
> New item - New prices.........
> http://www.visualmuses.com/chipcircuit/index.html
>
>
>
>
>
> [noparse][[/noparse]Non-text portions of this message have been removed]
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the
Subject and
> Body of the message will be ignored.
>
> Yahoo! Groups Links
> Not as elegant as some may wish but....
>
> Why not hack the remote that goes to that particular TV? All that would be
> necessary would be a small relay or perhaps a transistor across the "on"
> button of the remote.
If you don't want to (possibly) destroy your TV remote you could buy one of
the universal remotes from Radio Shack and hack it. Most remotes use a
keypad matrix to scan for key presses so you can't just send a hi or low to
simulate key presses. Instead you have to simulate connecting a row and col
together. I like using a CMOS cross point switch (like the MT8808:
<http://products.zarlink.com/product_profiles/MT8808.htm>). It digitally
accessible. ;-)
--
Enjoy,
George Warner,
Schizophrenic Optimization Scientists
Apple Developer Technical Support (DTS)
bjm1287@r... writes:
> Well...I'm using a Sharp TV...don't know much about the protocol, but
> I'll check into it. Just so we're on the same page, if I want the
> stamp to generate the IR, I've basically got to put an IR receiver on
> one of the input pins, and figure out how to measure (and store) the
> times that the pin is in a given state. Does that sound about right?
>
>
Not a receiver - a transmitter if you want to send a signal to your
television.
If the Sharp protocol is anything like Sony, then your narrow pulse has to be
.6ms in duration. You should be able to get pretty close to that with a
pulsout.
However, the pause between pulses is also .6ms and that it going to be tough
to control.
Sid Weaver
plug-in EEPROMs........
http://www.visualmuses.com/chipcircuit/index.html
[noparse][[/noparse]Non-text portions of this message have been removed]
I'll check into it. Just so we're on the same page, if I want the
stamp to generate the IR, I've basically got to put an IR receiver on
one of the input pins, and figure out how to measure (and store) the
times that the pin is in a given state. Does that sound about right?
Thanks,
--Brian
--- In basicstamps@yahoogroups.com, "Allan Lane" <allan.lane@h...>
wrote:
> There are MANY protocols for doing IR control
> of home audio/video electronics. Some are
> fairly easy, like the Sony protocol. Some
> are much harder.
>
> Basically, you want to output a 38 Khz signal
> 'pulse'. The duration of the 'pulse' and the
> duration of silence between pulses make up the
> protocol your TV or VCR understands.
>
> The easiest way to go about this is to buy a
> remote, set it for your television, then record
> the protocol is uses, then program that protocol
> into the BS2.
>
> It is doable, but not trivial. Search google for
> IR Sony Protocol, and IR Phillips RC-5 protocol.
> There are some very good web-sites out there with
> more info.
>
> --- In basicstamps@yahoogroups.com, "Brian M." <bjm1287@r...> wrote:
> > Hi all. I'm trying to find some documentation on transmitting IR
> > signals from a BS2. What I'm trying to accomplish is turning on
a
> TV
> > via IR when the stamp first turns on. I can find tons of
> information
> > on recieving IR data, but no examples of transmitting IR. Any
help
> > would be greatful.
> >
> > Thanks,
> > --Brian
One is an "IR Detector". These are designed to give
a pulse out when they recieve a pulse of 38 KHz
IR light. They actually have multiple models --
36 KHz, 38 KHz, 40 Khz, etc. I've found 38 KHz
tends to work well. You can detect and measure
its pulses with 'PULSIN'.
You can drive an IR LED (use a limiting resistor)
with FREQOUT to generate the pulses.
The other kind is an "IR Reciever". These merely
duplicate the blinks of IR light they recieve --
you would have to do the frequency detection yourself.
Most IR applications use an IR Detector, as they are
MUCH easier to interface with a Stamp. Give them
+5 and Ground, monitor their Signal line, and flash
your remote at it.
--- In basicstamps@yahoogroups.com, "Brian M." <bjm1287@r...> wrote:
> Well...I'm using a Sharp TV...don't know much about the protocol,
but
> I'll check into it. Just so we're on the same page, if I want the
> stamp to generate the IR, I've basically got to put an IR receiver
on
> one of the input pins, and figure out how to measure (and store)
the
> times that the pin is in a given state. Does that sound about
right?
>
> Thanks,
> --Brian
> --- In basicstamps@yahoogroups.com, "Allan Lane" <allan.lane@h...>
> wrote:
> > There are MANY protocols for doing IR control
> > of home audio/video electronics. Some are
> > fairly easy, like the Sony protocol. Some
> > are much harder.
> >
> > Basically, you want to output a 38 Khz signal
> > 'pulse'. The duration of the 'pulse' and the
> > duration of silence between pulses make up the
> > protocol your TV or VCR understands.
> >
> > The easiest way to go about this is to buy a
> > remote, set it for your television, then record
> > the protocol is uses, then program that protocol
> > into the BS2.
> >
> > It is doable, but not trivial. Search google for
> > IR Sony Protocol, and IR Phillips RC-5 protocol.
> > There are some very good web-sites out there with
> > more info.
> >
> > --- In basicstamps@yahoogroups.com, "Brian M." <bjm1287@r...>
wrote:
> > > Hi all. I'm trying to find some documentation on transmitting
IR
> > > signals from a BS2. What I'm trying to accomplish is turning
on
> a
> > TV
> > > via IR when the stamp first turns on. I can find tons of
> > information
> > > on recieving IR data, but no examples of transmitting IR. Any
> help
> > > would be greatful.
> > >
> > > Thanks,
> > > --Brian
No, you need a IR LED. You feed a PWM signal to a Schmitt type NAND on one
gate, and then the Stamp sends serial data to the other gate. This means
that pulses of PWM apperar on the output. This output drives the LED. For
best range you should switch the IR LED with a transistor. I usually don't
use a current limiting diode at all, as the duty cycle lets you get away
with it. The protocol used depends on the target device. Don't try to use a
regular NAND for this, it must be a Schmitt trigger NAND for good operation.
(74HC132)
HTH,
Jonathan
www.madlabs.info
Original Message
From: "Brian M." <bjm1287@r...>
To: <basicstamps@yahoogroups.com>
Sent: Monday, May 10, 2004 2:05 PM
Subject: [noparse][[/noparse]basicstamps] Re: IR question...
> Well...I'm using a Sharp TV...don't know much about the protocol, but
> I'll check into it. Just so we're on the same page, if I want the
> stamp to generate the IR, I've basically got to put an IR receiver on
> one of the input pins, and figure out how to measure (and store) the
> times that the pin is in a given state. Does that sound about right?
>
> Thanks,
> --Brian
> --- In basicstamps@yahoogroups.com, "Allan Lane" <allan.lane@h...>
> wrote:
> > There are MANY protocols for doing IR control
> > of home audio/video electronics. Some are
> > fairly easy, like the Sony protocol. Some
> > are much harder.
> >
> > Basically, you want to output a 38 Khz signal
> > 'pulse'. The duration of the 'pulse' and the
> > duration of silence between pulses make up the
> > protocol your TV or VCR understands.
> >
> > The easiest way to go about this is to buy a
> > remote, set it for your television, then record
> > the protocol is uses, then program that protocol
> > into the BS2.
> >
> > It is doable, but not trivial. Search google for
> > IR Sony Protocol, and IR Phillips RC-5 protocol.
> > There are some very good web-sites out there with
> > more info.
> >
> > --- In basicstamps@yahoogroups.com, "Brian M." <bjm1287@r...> wrote:
> > > Hi all. I'm trying to find some documentation on transmitting IR
> > > signals from a BS2. What I'm trying to accomplish is turning on
> a
> > TV
> > > via IR when the stamp first turns on. I can find tons of
> > information
> > > on recieving IR data, but no examples of transmitting IR. Any
> help
> > > would be greatful.
> > >
> > > Thanks,
> > > --Brian
>
>
>
> To UNSUBSCRIBE, just send mail to:
> basicstamps-unsubscribe@yahoogroups.com
> from the same email address that you subscribed. Text in the Subject and
Body of the message will be ignored.
>
> Yahoo! Groups Links
>
>
>
>
>
>
> I'll check into it. Just so we're on the same page, if I want the
> stamp to generate the IR, I've basically got to put an IR receiver on
> one of the input pins, and figure out how to measure (and store) the
> times that the pin is in a given state. Does that sound about right?
You can't just use an IR receiver since remotes typically modulate the IR.
What you want is one of the pre-packaged IR receivers / demodulators (Radio
Shack sells them). The output is a TTL signal that you can directly connect
to an input pin on your BS2.
--
Enjoy,
George Warner,
Schizophrenic Optimization Scientists
Apple Developer Technical Support (DTS)
> Hi all. I'm trying to find some documentation on transmitting IR
> signals from a BS2. ...
>
You should look at aricle #76 in Nuts & Volts, here is a link to it:
http://www.parallax.com/dl/docs/cols/nv/vol3/col/nv76.pdf
I used the info in the article and the links to decode the remote
for a DVD player and then reproduce the IR signals using a BS2sx to
control it.
JJ