Ability to drive multiple IR transmitters independantly from PC

[Alexis]

Hey guys,

I've got a situation where there's a number of identical displays in the
same area, and need to be able to switch them on and off individually
from a PC.

Currently there are 10 identical displays, which accept commands from a
remote control to switch on and off (discrete commands for each action).
I want something that I can connect up to a PC and will allow me to
switch on and off each display individually.

Obviously this means that there has to be ten IR transmitters, each
placed next to the sensor of the relevant display, and each of which can
be driven independantly (i.e. sending the same signal to all 10 will
result in all ten displays switching on/off - not the desired
functionality).

Whats more, the solution needs to be expandable to deal with up to
twenty such identical displays, all of which need to be individually
controlled.

I had considered using single USB IR transmitters, plugged into a USB
hub and then into the PC, but I doubt a single PC would be able to drive
20 such devices concurrently, not least of all because it would run out
of COM ports. So I'm looking for something which is designed to allow
control of multiple transmitters independantly.

Is there anything like this on the market? Ideally I'd like it to have
an API so that I can interface into it from my own code, but that's not
an essential requirement.

Any help appreciated!

[Bill Kearney]

> Is there anything like this on the market? Ideally I'd like it to have
> an API so that I can interface into it from my own code, but that's not
> an essential requirement.

I'd have to guess that Xantech has something that could be put together to
setup the necessary zones. Likewise also arrange a PC interface.
www.xantech.com

[ved_dhuru@hotmail.com]

Hi,

> I've got a situation where there's a number of identical displays in the
> same area, and need to be able to switch them on and off individually
> from a PC.
>
> Currently there are 10 identical displays, which accept commands from a
> remote control to switch on and off (discrete commands for each action).
> I want something that I can connect up to a PC and will allow me to
> switch on and off each display individually.

If I understand the above, you just want to swicth the displays on and
off; not control any other parameter. In which case, why not just
switch the power?

This would be fairly trivial upto 8 channels by simply using the PC's
parallel ports to drive a couple of relays; there are a few utilities
that let you do exactly that; control each bit on the port. Beyond
that, you could use a PIC with lots of outputs, and connect it to the
PC over the serial port. The PC indicates to the PI(C what to do with
each i/o bit.

Regards,

Anand

[ved_dhuru@hotmail.com]

Sorry, intended to include this link the last post:

http://www.rentron.com/sending_data.htm

This is pretty much what i had in mind, just scale it up to a larger
PIC for more channels that you mentioned.

Regards,

Anand Dhuru


ved_dh...@hotmail.com wrote:
> Hi,
>
> > I've got a situation where there's a number of identical displays in the
> > same area, and need to be able to switch them on and off individually
> > from a PC.
> >
> > Currently there are 10 identical displays, which accept commands from a
> > remote control to switch on and off (discrete commands for each action).
> > I want something that I can connect up to a PC and will allow me to
> > switch on and off each display individually.
>
> If I understand the above, you just want to swicth the displays on and
> off; not control any other parameter. In which case, why not just
> switch the power?
>
> This would be fairly trivial upto 8 channels by simply using the PC's
> parallel ports to drive a couple of relays; there are a few utilities
> that let you do exactly that; control each bit on the port. Beyond
> that, you could use a PIC with lots of outputs, and connect it to the
> PC over the serial port. The PC indicates to the PI(C what to do with
> each i/o bit.
>
> Regards,
>
> Anand

[Dave Houston]

Alexis <snoopy@alexSiPsAbMirkill.com> wrote:

>Hey guys,
>
>I've got a situation where there's a number of identical displays in the
>same area, and need to be able to switch them on and off individually
>from a PC.
>
>Currently there are 10 identical displays, which accept commands from a
>remote control to switch on and off (discrete commands for each action).
>I want something that I can connect up to a PC and will allow me to
>switch on and off each display individually.
>
>Obviously this means that there has to be ten IR transmitters, each
>placed next to the sensor of the relevant display, and each of which can
>be driven independantly (i.e. sending the same signal to all 10 will
>result in all ten displays switching on/off - not the desired
>functionality).
>
>Whats more, the solution needs to be expandable to deal with up to
>twenty such identical displays, all of which need to be individually
>controlled.
>
>I had considered using single USB IR transmitters, plugged into a USB
>hub and then into the PC, but I doubt a single PC would be able to drive
>20 such devices concurrently, not least of all because it would run out
>of COM ports. So I'm looking for something which is designed to allow
>control of multiple transmitters independantly.
>
>Is there anything like this on the market? Ideally I'd like it to have
>an API so that I can interface into it from my own code, but that's not
>an essential requirement.
>
>Any help appreciated!

What's the distance from PC to displays?

USB has limited distance on the USB cable length. However, you could use an
external IR emitter with a long lead. This may require disabling the
internal emitter to prevent it from affecting multiple receivers.

The question is whether the PC can distinguish between multiple USB IR
modules.

I would ask the designer of USB-UIRT if you can use multiples. If so there
is an API for these devices and they are reasonably priced.

http://www.usbuirt.com/

Is it possible to change the code that each display responds to? If so, you
only need one IR unit.

http://davehouston.net
http://tech.groups.yahoo.com/group/roZetta/
roZetta-subscribe@yahoogroups.com

[ved_dhuru@hotmail.com]

Ok, here's another approach; a hybrid of dave's solution and mine.

Use my solution (above) to select the channel, and the particular relay
drives the USB IR's IR LED. You would then need only 1 USB IR. You
would have to hack it to get to the IR LED output.

On the PC, you'd need two commnads to be sent; channel select and
on/off.

Also, you would have 1 transmitter per display, so the concerns that
Dave mentioned would come into play unless you shield each LED and
leave a very narrow aperture, and then place it in close proximity of
the individual displays. I have had excellent results using black
heat-shrnkable tubing to achieve this.

Regards,

Anand


Dave Houston wrote:
> Alexis <snoopy@alexSiPsAbMirkill.com> wrote:
>
> >Hey guys,
> >
> >I've got a situation where there's a number of identical displays in the
> >same area, and need to be able to switch them on and off individually
> >from a PC.
> >
> >Currently there are 10 identical displays, which accept commands from a
> >remote control to switch on and off (discrete commands for each action).
> >I want something that I can connect up to a PC and will allow me to
> >switch on and off each display individually.
> >
> >Obviously this means that there has to be ten IR transmitters, each
> >placed next to the sensor of the relevant display, and each of which can
> >be driven independantly (i.e. sending the same signal to all 10 will
> >result in all ten displays switching on/off - not the desired
> >functionality).
> >
> >Whats more, the solution needs to be expandable to deal with up to
> >twenty such identical displays, all of which need to be individually
> >controlled.
> >
> >I had considered using single USB IR transmitters, plugged into a USB
> >hub and then into the PC, but I doubt a single PC would be able to drive
> >20 such devices concurrently, not least of all because it would run out
> >of COM ports. So I'm looking for something which is designed to allow
> >control of multiple transmitters independantly.
> >
> >Is there anything like this on the market? Ideally I'd like it to have
> >an API so that I can interface into it from my own code, but that's not
> >an essential requirement.
> >
> >Any help appreciated!
>
> What's the distance from PC to displays?
>
> USB has limited distance on the USB cable length. However, you could use an
> external IR emitter with a long lead. This may require disabling the
> internal emitter to prevent it from affecting multiple receivers.
>
> The question is whether the PC can distinguish between multiple USB IR
> modules.
>
> I would ask the designer of USB-UIRT if you can use multiples. If so there
> is an API for these devices and they are reasonably priced.
>
> http://www.usbuirt.com/
>
> Is it possible to change the code that each display responds to? If so, you
> only need one IR unit.
>
> http://davehouston.net
> http://tech.groups.yahoo.com/group/roZetta/
> roZetta-subscribe@yahoogroups.com

[Frank Mc Alinden]

Hi Alexis

Just a pity it wasnt multiples of 8 devices......

If so you could use my FirM hardware (which was initiailly designed for Homevision HA Controller ,BUT would require a homebrew serial interface) ..You would also require a USBUIRT to learn and generate the ir signal...

You could still use the USBUIRT and Make up a Homebrew serial interface which the computer sends commands to it to tell it which zone the ir signal is going to then send via the USBUIRT.....

http://www.armaghelectrical.com.au/page7.html

http://www.usbuirt.com/

HTH
Frank

[Alexis]

ved_dhuru@hotmail.com wrote:
> If I understand the above, you just want to swicth the displays on and
> off; not control any other parameter. In which case, why not just
> switch the power?

Hi Anand,

That's a very good question, and one I should have clarified in the
original post - the displays in question are projectors, and as such,
cutting the power to them without allowing them to shut down correctly
drastically reduces the lifetime of the bulb. When they receive the
'off' IR signal, they enter a rapid cool-down mode lasting about 2
minutes, where the cooling fan runs constantly.

In addition, I believe that they do not default to the 'on' state when
power is initially applied.

Thanks,

Alexis.

[Alexis]

Dave Houston wrote:
> What's the distance from PC to displays?

Ranging from about 5 metres to about 20 metres - I had planned to either
use USB repeaters or IR LEDs on a long bit of wire, either of which
should be adequate workarounds for the distance, I hope.

> I would ask the designer of USB-UIRT if you can use multiples. If so there
> is an API for these devices and they are reasonably priced.

My concern with this solution is that it will probably work for a small
number of devices, but I have concerns as to whether it will work with
the full complement of 20 devices. I am unsure as to how the USB UIRT
device interfaces with the PC. If it acts as a virtual serial port, I
suspect this may be an issue, as Windows will, as far as I know, only
support a maximum of 16 COM ports active at any time. (For the record,
using Linux is sadly not an option in this case).

If anyone can clarify whether this would or would not be a problem, I
would be interested - at the moment this is only my guesswork, but it's
an expensive experiment to find out if I'm right!

> Is it possible to change the code that each display responds to? If so, you
> only need one IR unit.

Sadly not - they are identical and there is no support for coding of the
IR transmitters and receivers.

Thanks!

Alexis.

[Alexis]

Bill Kearney wrote:
> I'd have to guess that Xantech has something that could be put together to
> setup the necessary zones. Likewise also arrange a PC interface.
> www.xantech.com

Thanks Bill - their IR Router seems to do the majority of what I need,
although by the look of it I'd need to send it IR commands to switch
between channels - but this wouldn't be out of the question.

It is quite an expensive solution though, especially as a single 8 port
device wouldn't quite cope with the 10 existing displays, necessitating
two. I also need to read up more on how to control two routers
independantly. But it's a promising possibility!

Thanks again!

Alexis.

[Alexis]

ved_dhuru@hotmail.com wrote:
> Ok, here's another approach; a hybrid of dave's solution and mine.
>
> Use my solution (above) to select the channel, and the particular relay
> drives the USB IR's IR LED. You would then need only 1 USB IR. You
> would have to hack it to get to the IR LED output.
>
> On the PC, you'd need two commnads to be sent; channel select and
> on/off.

Hi again Anand,

Now that is a very interesting solution, that I hadn't considered at
all. It has the slight downside that global device control (i.e.
switching on or off multiple devices simultaneously) takes a little
longer, but the time taken should be acceptable.

I especially like that it is effectively infinitely expandable, as you
would just need additional switching relays. Do you happen to know if
there are any schematics detailing how such a switching system might be
implemented online? I will have a look myself later tonight.

> Also, you would have 1 transmitter per display, so the concerns that
> Dave mentioned would come into play unless you shield each LED and
> leave a very narrow aperture, and then place it in close proximity of
> the individual displays. I have had excellent results using black
> heat-shrnkable tubing to achieve this.

This isn't too much of a concern due to them being projectors - they
have two IR reciever windows to allow them to be controlled from
multiple angles, so it's no issue to tape the IR transmitting LED to be
in direct contact with the IR receiving window, and block it out from
transmitting elsewhere.

Thanks again!

Alexis.

[Alexis]

Frank Mc Alinden wrote:
> Hi Alexis
>
> Just a pity it wasnt multiples of 8 devices......
>
> If so you could use my FirM hardware (which was initiailly designed
> for Homevision HA Controller ,BUT would require a homebrew serial
> interface) ..You would also require a USBUIRT to learn and generate
> the ir signal...

Hi Frank,

I actually came across your system last night after posting, and it did
seem to have a number of characteristics that would make it very
suitable for this application. Unfortunately, the cost is the main
prohibiter - am I correct in estimating the cost of controlling 10
devices as being:

2 x FirM controller @ $275.00 = $550.00
10 x FirM zone receiver @ $60.00 = $600.00

Total cost $1150.00

Unfortunately that's a little more than I'd ideally like to spend,
although I appreciate that it's worth the price for the flexibility, and
I love the ability to hook up receivers using simple CAT5 cabling. I
also appreciate the cost would have been significantly less if there
were only 8 devices to control!

Many thanks,

Alexis.

[Dave Houston]

Alexis <snoopy@alexSiPsAbMirkill.com> wrote:

>Dave Houston wrote:
>> What's the distance from PC to displays?
>
>Ranging from about 5 metres to about 20 metres - I had planned to either
>use USB repeaters or IR LEDs on a long bit of wire, either of which
>should be adequate workarounds for the distance, I hope.

USB repeaters are costly compared to long IRED leads.

>> I would ask the designer of USB-UIRT if you can use multiples. If so there
>> is an API for these devices and they are reasonably priced.
>
>My concern with this solution is that it will probably work for a small
>number of devices, but I have concerns as to whether it will work with
>the full complement of 20 devices. I am unsure as to how the USB UIRT
>device interfaces with the PC. If it acts as a virtual serial port, I
>suspect this may be an issue, as Windows will, as far as I know, only
>support a maximum of 16 COM ports active at any time. (For the record,
>using Linux is sadly not an option in this case).

Windows supports 256 COM ports so this should not be a problem. However,
although they use FTDI USB-serial chips, I don't think USB-UIRT uses virtual
serial ports. That's why I suggested you contact them to be sure they can
distinguish between 20 devices. I believe FTDI provides for this by giving
you a way to assign an ID to each device but its been too long since I
looked at the details. (These days, a few hours is too long.:()



http://davehouston.net
http://tech.groups.yahoo.com/group/roZetta/
roZetta-subscribe@yahoogroups.com

[Dave Houston]

Alexis <snoopy@alexSiPsAbMirkill.com> wrote:

>Total cost $1150.00
>
>Unfortunately that's a little more than I'd ideally like to spend,
>although I appreciate that it's worth the price for the flexibility, and
>I love the ability to hook up receivers using simple CAT5 cabling. I
>also appreciate the cost would have been significantly less if there
>were only 8 devices to control!

Since you were talking about USB repeaters I assumed cost was not a factor.

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?

http://davehouston.net
http://tech.groups.yahoo.com/group/roZetta/
roZetta-subscribe@yahoogroups.com

[Alexis]

Dave Houston wrote:
> Windows supports 256 COM ports so this should not be a problem. However,
> although they use FTDI USB-serial chips, I don't think USB-UIRT uses virtual
> serial ports. That's why I suggested you contact them to be sure they can
> distinguish between 20 devices. I believe FTDI provides for this by giving
> you a way to assign an ID to each device but its been too long since I
> looked at the details. (These days, a few hours is too long.:()

Hi Dave,

That's interesting, thanks. I shall definitely get in touch with them
and see if they can clarify the maximum number of devices a single PC
can realistically support.

Cheers,

Alexis.

[Alexis]

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!

Thanks again,

Alexis.

[Dave Houston]

Alexis <snoopy@alexSiPsAbMirkill.com> 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/
roZetta-subscribe@yahoogroups.com

[Dave Houston]

Alexis <snoopy@alexSiPsAbMirkill.com> wrote:

>> 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?

If I had $70000 worth of projectors I'd probably feel I had enough clout
with whatever dealer sold them to get the IR codes. ;-)

http://davehouston.net
http://tech.groups.yahoo.com/group/roZetta/
roZetta-subscribe@yahoogroups.com

[Robert L Bass]

I did a little research and here's what I found out so far.

PC serial codes:

POWER ON 02H 00H 00H 00H 00H 02H
POWER OFF 02H 01H 00H 00H 00H 03H
INPUT SELECT COMPUTER 02H 03H 00H 00H 02H 01H 01H 09H
INPUT SELECT VIDEO 02H 03H 00H 00H 02H 01H 06H 0EH
INPUT SELECT S-VIDEO 02H 03H 00H 00H 02H 01H 0BH 13H
INPUT SELECT DVI (DIGITAL) 02H 03H 00H 00H 02H 01H 1AH 22H
PICTURE MUTE ON 02H 10H 00H 00H 00H 12H
PICTURE MUTE OFF 02H 11H 00H 00H 00H 13H
SOUND MUTE ON 02H 12H 00H 00H 00H 14H
SOUND MUTE OFF 02H 13H 00H 00H 00H 15H
PROJECTOR INFORMATION REQUEST 00H BFH 00H 00H 01H 02H C2H
ERROR STATUS REQUEST 00H 88H 00H 00H 00H 88H
INFORMATION REQUEST 03H 8AH 00H 00H 00H 8DH

IR Codes:
Power On: F7
Power Off: EB
Enter: E8
Cancel: DA
Menu: B9
Help: B1

There are more. If you need them, let me know.

Hope that helps.

--

Regards,
Robert L Bass

=============================>
Bass Home Electronics
941-866-1100
4883 Fallcrest Circle
Sarasota · Florida · 34233
http://www.bassburglaralarms.com
=============================>

>>> 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?
>
> If I had $70000 worth of projectors I'd probably feel I had enough clout
> with whatever dealer sold them to get the IR codes. ;-)
>
> http://davehouston.net
> http://tech.groups.yahoo.com/group/roZetta/
> roZetta-subscribe@yahoogroups.com

[B Fuhrmann]

"Alexis" wrote...

> Currently there are 10 identical displays, which accept commands from a
> remote control to switch on and off (discrete commands for each action). I
> want something that I can connect up to a PC and will allow me to switch
> on and off each display individually.

What program in the computer will do the control? Is the computer deciding
when each projector gets tuned on/off?
If not, have you considered a box with 20 buttons, one for each projector?

Since you don't need "any and all" commands to be sent to the projectors,
you could use a remote (or something that can learn the IR pattern) with a
long wire between the LED and the remote, then a signal from whatever the
triggers the remote.

If all the projectors respond to the same signal, one remote could be wired
to all the LEDs (with appropriate buffering) via a control matrix that would
connect the remote to the correct LED(s) and triggers the remote.
That could be done without a computer (a small amount of logic and some
transistors) or could be done with a simple digital output card.

--
Bill Fuhrmann

[Dave Houston]

Alexis <snoopy@alexSiPsAbMirkill.com> wrote:

>Dave Houston wrote:
>> Windows supports 256 COM ports so this should not be a problem. However,
>> although they use FTDI USB-serial chips, I don't think USB-UIRT uses virtual
>> serial ports. That's why I suggested you contact them to be sure they can
>> distinguish between 20 devices. I believe FTDI provides for this by giving
>> you a way to assign an ID to each device but its been too long since I
>> looked at the details. (These days, a few hours is too long.:()
>
>Hi Dave,
>
>That's interesting, thanks. I shall definitely get in touch with them
>and see if they can clarify the maximum number of devices a single PC
>can realistically support.

Here are the FTDI ID details from an app note on their website.

<quote>
Each FT232R USB UART IC and FT245R USB FIFO IC has a unique identification
number burnt into it during manufacture, the FTDIChip-ID.

The FTDIChip-ID is readable over USB, but cannot be altered by the end user.
This feature provides a way of tying application software to a specific
device with a high level of security.

The FTDIChip-ID feature can be used without affecting any of the other
device features.
</quote>



http://davehouston.net
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roZetta-subscribe@yahoogroups.com

[Dave Houston]

Alexis <snoopy@alexSiPsAbMirkill.com> wrote:

>Dave Houston wrote:

>> 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?

The RS232 serial commands are listed in the user manual. I would forget
about IR.

You can get single port USB-serial adapters for $10 each. Run 4-wire modular
cable from the RS232 end of each adapter to each projector. Cost: $10 +
cable + connectors per projector. The only problem is getting 20 USB ports
to plug the adapters into. I have 4-port USB expanders on a couple of
machines but I haven't seen a 10-port or 20-port version.

http://www.byterunner.com/byterunner/product_name=Y-105/user-id=/password=/exchange=/exact_match=exact

http://davehouston.net
http://tech.groups.yahoo.com/group/roZetta/
roZetta-subscribe@yahoogroups.com

[Frank Mc Alinden]

Hi Alexis

I think (IMHO) the cheapest way forward would be to purchase a USBUIRT

Then make your own Homebrew Transmitter Zone Selector using say a pic micro.. Or connect the USBUIRT output to something like this...

http://www.oceancontrols.com.au/controllers/serial_daq_k108.htm

The ir output of the USBUIRT connects to all relay commons ....To send ir to a set zone firstly send a command to the serial device to turn ON 1 output and then send the ir signal via the USBUIRT then turn the zone relay off .....??...Looks like you can connect multiples of this serial device to a single serial port.....

Also with my FirM Kit if using only the Transmitter function no FirM Receivers required.......but as i mentione a serial interface would be required....

HTH
Frank

[nature_girl90@hotmail.com]

Alexis wrote:
> ved_dhuru@hotmail.com wrote:
> > Ok, here's another approach; a hybrid of dave's solution and mine.
> >
> > Use my solution (above) to select the channel, and the particular relay
> > drives the USB IR's IR LED. You would then need only 1 USB IR. You
> > would have to hack it to get to the IR LED output.
> >
> > On the PC, you'd need two commnads to be sent; channel select and
> > on/off.
>
> Hi again Anand,
>
> Now that is a very interesting solution, that I hadn't considered at
> all. It has the slight downside that global device control (i.e.
> switching on or off multiple devices simultaneously) takes a little
> longer, but the time taken should be acceptable.

Alexis, global commands should not be a problem if you incorporate them
in the VB program running on the PC (Channel1, Channel2, ....All
Channels, something like the All Lights ON in X10), and program the PIC
to respond to that, besides the individual pin control.

>
> I especially like that it is effectively infinitely expandable, as you
> would just need additional switching relays.

Yes; you would only be restricted by the number of I/O pins available
on the PIC. For a standard 40 pin that would be about 33 channels! And
of course you could use even more PICs, if required, each having its
own address.

Do you happen to know if
> there are any schematics detailing how such a switching system might be
> implemented online? I will have a look myself later tonight.
>
Are you referring to the hardware (PIC, Relay, USBIR hack) or the
(Serial port, PIC)?

You'll find a lot of answers on the URL I gave above.

This is getting interesting. I'd love to help you all I can, so feel
free to ask for more details. I'm travelling over the week-end, though,
so I can only repond on Monda/Tuesday.

Regards,

Anand


> This isn't too much of a concern due to them being projectors - they
> have two IR reciever windows to allow them to be controlled from
> multiple angles, so it's no issue to tape the IR transmitting LED to be
> in direct contact with the IR receiving window, and block it out from
> transmitting elsewhere.
>
> Thanks again!
>
> Alexis.

[JS]

Here's two more approaches to add to the equation... 1) Use 3 JDS IRXP2
Infrared Xpanders. Each has 4 individually addressable IR outputs
(3.5mm jacks). You'll need 3 serial ports on your pc (or 3
USB-to-serial adapters). 2) Use 1 JDS IRXP2 Infrared Xpander and wire
the 4 outputs to a 74HC154 4-to-16 line decoder chip. The output of
the 74HC154 can provide up to 15 outputs.

Alexis wrote:
> Hey guys,
>
> I've got a situation where there's a number of identical displays in the
> same area, and need to be able to switch them on and off individually
> from a PC.
>
> Currently there are 10 identical displays, which accept commands from a
> remote control to switch on and off (discrete commands for each action).
> I want something that I can connect up to a PC and will allow me to
> switch on and off each display individually.
>
> Obviously this means that there has to be ten IR transmitters, each
> placed next to the sensor of the relevant display, and each of which can
> be driven independantly (i.e. sending the same signal to all 10 will
> result in all ten displays switching on/off - not the desired
> functionality).
>
> Whats more, the solution needs to be expandable to deal with up to
> twenty such identical displays, all of which need to be individually
> controlled.
>
> I had considered using single USB IR transmitters, plugged into a USB
> hub and then into the PC, but I doubt a single PC would be able to drive
> 20 such devices concurrently, not least of all because it would run out
> of COM ports. So I'm looking for something which is designed to allow
> control of multiple transmitters independantly.
>
> Is there anything like this on the market? Ideally I'd like it to have
> an API so that I can interface into it from my own code, but that's not
> an essential requirement.
>
> Any help appreciated!

[Dave Houston]

nobody@whocares.com (Dave Houston) wrote:


>The RS232 serial commands are listed in the user manual. I would forget
>about IR.
>
>You can get single port USB-serial adapters for $10 each. Run 4-wire modular
>cable from the RS232 end of each adapter to each projector. Cost: $10 +
>cable + connectors per projector. The only problem is getting 20 USB ports
>to plug the adapters into. I have 4-port USB expanders on a couple of
>machines but I haven't seen a 10-port or 20-port version.
>
>http://www.byterunner.com/byterunner/product_name=Y-105/user-id=/password=/exchange=/exact_match=exact

An more costly alternative, if the PC has enough ISA or PCI slots available,
is to do it with true RS232 ports using Byterunner 8-port serial cards.

http://www.byterunner.com/byterunner/category=8+Serial+(RS-232)+ISA-bus+cards/exact_match=exact
http://www.byterunner.com/byterunner/category=8+Serial+(RS-232)+PCI-bus+cards/exact_match=exact

http://davehouston.net
http://tech.groups.yahoo.com/group/roZetta/
roZetta-subscribe@yahoogroups.com

[Bill Kearney]

> You can get single port USB-serial adapters for $10 each. Run 4-wire
modular
> cable from the RS232 end of each adapter to each projector. Cost: $10 +
> cable + connectors per projector. The only problem is getting 20 USB ports
> to plug the adapters into. I have 4-port USB expanders on a couple of
> machines but I haven't seen a 10-port or 20-port version.

If you're going with serial get some EdgePort multiport adapters. I've used
their 4 and 8 port adapters and they're GREAT. It's MUCH better than using
multiple single USB-serial adapters, if only because of avoiding the
software driver NIGHTMARES. Get two 8 port and one 4 port adapter and only
have to use ONE software driver and three USB ports, most likely just
chained to a single hub.

[Reg]

Bill Kearney wrote:

>>You can get single port USB-serial adapters for $10 each. Run 4-wire
>
> modular
>
>>cable from the RS232 end of each adapter to each projector. Cost: $10 +
>>cable + connectors per projector. The only problem is getting 20 USB ports
>>to plug the adapters into. I have 4-port USB expanders on a couple of
>>machines but I haven't seen a 10-port or 20-port version.
>
>
> If you're going with serial get some EdgePort multiport adapters. I've used
> their 4 and 8 port adapters and they're GREAT. It's MUCH better than using
> multiple single USB-serial adapters, if only because of avoiding the
> software driver NIGHTMARES. Get two 8 port and one 4 port adapter and only
> have to use ONE software driver and three USB ports, most likely just
> chained to a single hub.
>

Agree on all counts. The Edgeport made my life a lot simpler.

I got my 8 port very cheap on ebay.

--
Reg

[Dan Lanciani]

In article <457a08f5.465820843@nntp.fuse.net>, nobody@whocares.com (Dave Houston) writes:
| Alexis <snoopy@alexSiPsAbMirkill.com> wrote:
|
| >Dave Houston wrote:
|
| >> 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?
|
| The RS232 serial commands are listed in the user manual. I would forget
| about IR.
|
| You can get single port USB-serial adapters for $10 each. Run 4-wire modular
| cable from the RS232 end of each adapter to each projector. Cost: $10 +
| cable + connectors per projector. The only problem is getting 20 USB ports
| to plug the adapters into. I have 4-port USB expanders on a couple of
| machines but I haven't seen a 10-port or 20-port version.

Another possibility would be to use one or more Ethernet terminal servers.
IOLAN 16-port units can often be had cheaply on eBay. They can be configured
to provide a transparent tcp/ip connection to each RS232 port. The application
on the PC would open one socket for each projector connection. An advantage is
that all you need on the PC is a standard Ethernet port.

Dan Lanciani
ddl@danlan.*com

[Dave Houston]

"Bill Kearney" <wkearney99@hotmail.com> wrote:

>> You can get single port USB-serial adapters for $10 each. Run 4-wire
>modular
>> cable from the RS232 end of each adapter to each projector. Cost: $10 +
>> cable + connectors per projector. The only problem is getting 20 USB ports
>> to plug the adapters into. I have 4-port USB expanders on a couple of
>> machines but I haven't seen a 10-port or 20-port version.
>
>If you're going with serial get some EdgePort multiport adapters. I've used
>their 4 and 8 port adapters and they're GREAT. It's MUCH better than using
>multiple single USB-serial adapters, if only because of avoiding the
>software driver NIGHTMARES. Get two 8 port and one 4 port adapter and only
>have to use ONE software driver and three USB ports, most likely just
>chained to a single hub.

Bill, you sure have a lot of nightmares where others just have have sweet
dreams - perhaps you should lay off the late night stacks. The single port
adapters will use ONE DRIVER and cost less than the multi-port units. (At
least, they cost much less, about 1/2 as much per port, than the multi-port
units offered by Byterunner.)

In any event, Dan Lanciani's ethernet-serial suggestion, since it only needs
one ethernet port, is probably the easiest way to go if you can find a cheap
used unit. I don't usually recommend eBay because I prefer to look my fence
in the eye when he tells me, "It fell off a truck". ;)

http://davehouston.net
http://tech.groups.yahoo.com/group/roZetta/
roZetta-subscribe@yahoogroups.com

[Bill Kearney]

> Bill, you sure have a lot of nightmares where others just have have sweet
> dreams - perhaps you should lay off the late night stacks. The single port
> adapters will use ONE DRIVER and cost less than the multi-port units. (At
> least, they cost much less, about 1/2 as much per port, than the
multi-port
> units offered by Byterunner.)

Assuming you make use of single port devices all from the same vendor and
the then the same model/production run. While a number of them do base
themselves on the same chipsets not all make use of the same driver
software, and some are worse than others. Then there's the USB bandwidth
and power issues. There you're running up against how well (or poorly) the
hardware and drivers for the USB ports are set up.

I'll trade time wasted wrestling with bad drivers for a few extra bucks on a
multi-port instead.

[Dave Houston]

"Bill Kearney" <wkearney99@hotmail.com> wrote:
>
>Assuming you make use of single port devices all from the same vendor and
>the then the same model/production run. While a number of them do base
>themselves on the same chipsets not all make use of the same driver
>software, and some are worse than others. Then there's the USB bandwidth
>and power issues. There you're running up against how well (or poorly) the
>hardware and drivers for the USB ports are set up.

BULL!

Under Windows...

ALL FTDI chipsets work with the same drivers. (They offer both VCP and a
direct interface with an API - the device developer chooses which.) ALL
SiliconLabs chips work with the same driver. I haven't tried anything with
the Prolific chipset but the fact they offer only one driver speaks to the
fact that they must all work with that one driver.

I have used multi-port hubs. If you search, you will find I was the first to
post about them here several years ago. The Entrega (later Xircom, later
Intel) 4U2S1P hub was one of the earliest. There's absolutely no difference
in operation between the serial ports on such hubs and multiple single port
adapters from the same manufacturer which is exactly what I recommended,
even giving a URL to the specific adapter.

I have an adapter made by FTDI using their very first chipset. (I think I
was the first to post here about them.) It works with the same driver as any
using their latest chips as well as any in between. I have 3 different
SiliconLabs chips (CP2101, CP2102, CP2103). All use the same driver.

I have had an FTDI based adapter, 2 SiliconLabs based adapters, the Entrega
hub with two USB-serial ports, a USB-UIRT (uses a later FTDI chipset) and a
Byterunner 8-port PCI card on the same PC along with two motherboard serial
ports with absolutely none of the fictional driver "nightmares" you predict.
Windows finds the new hardware, asks for a disk if it doesn't already have a
driver, installs the driver once (if needed) and operation is transparent
and uneventful thereafter.

I have reassigned port names to test that my software can enumerate and
connect to COM1-COM99.

I believe the FTDI and SiliconLabs drivers have been added to the Linux
kernel. The FTDI drivers are included in XP.

Macs never had true serial ports and some of the USB-serial adapters
originally designed for that market are the ones most often complained about
by folks who try using them with PCs and applications that need all of the
handshaking lines.


http://davehouston.net
http://tech.groups.yahoo.com/group/roZetta/
roZetta-subscribe@yahoogroups.com

[Bill Kearney]

> >Assuming you make use of single port devices all from the same vendor and
> >the then the same model/production run. While a number of them do base
> >themselves on the same chipsets not all make use of the same driver
> >software, and some are worse than others. Then there's the USB bandwidth
> >and power issues. There you're running up against how well (or poorly)
the
> >hardware and drivers for the USB ports are set up.
>
> BULL!

You've named at least three chipsets, I'm sure there are more. I've worked
with quite a few of these adapters over the years (from at least a dozen
different vendors) and have had very little success with getting most
software working with them on a consistent basis. There's plenty of points
of blame possible, from the software itself doing a bad job of just using
serial ports, hardware conflicts (irqs, etc) and that's all before getting
to the USB driver's layer. So in the real world there's lots of room for
problems. Thus having found success using multiport adapters I'm given to
encouraging others to trying it.

> I have used multi-port hubs.

I'm not talking about hubs. I'm sure you're delighted with your vast array
of knowledge, thanks for sharing.

> Macs never had true serial ports

Well, here you're plainly wrong. Granted, they weren't PC comm ports in the
traditional sense but all (nearly?) pre-USB macintoshes came with two serial
ports. 422 capable as well.

[Dave Houston]

"Bill Kearney" <wkearney99@hotmail.com> wrote:

>You've named at least three chipsets, I'm sure there are more. I've worked
>with quite a few of these adapters over the years (from at least a dozen
>different vendors) and have had very little success with getting most
>software working with them on a consistent basis. There's plenty of points
>of blame possible, from the software itself doing a bad job of just using
>serial ports, hardware conflicts (irqs, etc) and that's all before getting
>to the USB driver's layer. So in the real world there's lots of room for
>problems. Thus having found success using multiport adapters I'm given to
>encouraging others to trying it.

And I've never experienced any such difficulties. Go figure.

>> I have used multi-port hubs.
>
>I'm not talking about hubs. I'm sure you're delighted with your vast array
>of knowledge, thanks for sharing.
>
>> Macs never had true serial ports
>
>Well, here you're plainly wrong. Granted, they weren't PC comm ports in the
>traditional sense but all (nearly?) pre-USB macintoshes came with two serial
>ports. 422 capable as well.

They had RS422 ports which use balanced signals. That's closer to RS485 than
to RS232 which uses unbalanced signals. Most people would regard RS232 as
"serial".

http://davehouston.net
http://tech.groups.yahoo.com/group/roZetta/
roZetta-subscribe@yahoogroups.com

[Bill Kearney]

> >> Macs never had true serial ports
> >
> >Well, here you're plainly wrong. Granted, they weren't PC comm ports in
the
> >traditional sense but all (nearly?) pre-USB macintoshes came with two
serial
> >ports. 422 capable as well.
>
> They had RS422 ports which use balanced signals. That's closer to RS485
than
> to RS232 which uses unbalanced signals. Most people would regard RS232 as
> "serial".

The ports would do RS232 just fine, this in addition to being able to do
their Localtalk/Appletalk scheme based. What this has to do with USB-serial
adapters is anyone's guess...