RS-232 DB25 Breakout strip

[Robert Green]

Anyone know of a place to acquire a male DB-25 connector that fans out to a
25 terminal screw strip? I've got a video switcher that's got a DB25 female
connector on the back that carries various input and output signals as well
as an RS-232 connection. I want to be able to change connections to the
unit fairly easily so I would like to have a connector plug into the MUX and
then have it feed into a project box containing the terminal strips.

TIA

--
Bobby G.

[Dave Houston]

Try B&B Electronics. They used to have them.

"Robert Green" <ROBERT_GREEN1963@YAH00.COM> wrote:

>Anyone know of a place to acquire a male DB-25 connector that fans out to a
>25 terminal screw strip? I've got a video switcher that's got a DB25 female
>connector on the back that carries various input and output signals as well
>as an RS-232 connection. I want to be able to change connections to the
>unit fairly easily so I would like to have a connector plug into the MUX and
>then have it feed into a project box containing the terminal strips.
>
>TIA

[Robert Green]

"Dave Houston" <nobody@whocares.com> wrote

> Try B&B Electronics. They used to have them.

Wow! Look at all the serial-flavored goodies!

http://www.bb-elec.com/

Plus, lots of technical information that I'm going to need about connecting
RS-232 and 485 devices. That will be handy because in addition to the
RS-232 control input, these MUX boxes have a RS-485 port to connect to each
other.

Lots of other information including the story behind the gradual
disappearance of serial ports from PC's:

http://www.bb-elec.com/tech_articles/diappearing_com_ports.asp

"A "Legacy Removal Roadmap" has been established at the Intel Developers
Forum in 1999 for the phasing out of "Legacy Technologies" in PCs. The first
to go in this timeline was the ISA slot, used for adding special function
cards to the available PC slots. Intel's Legacy Removal Roadmap calls for
the gradual phase out of other technologies. On the list for removal are the
following: Gameport/MIDI, PS2, Serial, Parallel, IDE, Floppy, VGA, and
eventually all user-accessible slots."

Oy!

Still looking for the breakout connector but I am sure it's here somewhere .
.. .

--
Bobby G.

[Dave Houston]

"Robert Green" <ROBERT_GREEN1963@YAH00.COM> wrote:

>Still looking for the breakout connector but I am sure it's here somewhere

That may be a product whose time has passed and that they've dropped.

[Dave Houston]

"Robert Green" <ROBERT_GREEN1963@YAH00.COM> wrote:

>Still looking for the breakout connector but I am sure it's here somewhere .

http://www.winfordeng.com/products/brk25.php

They have breakout boards of almost every possible type.

[Robert Green]

"Dave Houston" <nobody@whocares.com> wrote in message
news:43d676e2.398215843@nntp.fuse.net...
> "Robert Green" <ROBERT_GREEN1963@YAH00.COM> wrote:
>
> >Still looking for the breakout connector but I am sure it's here
somewhere .
>
> http://www.winfordeng.com/products/brk25.php
>
> They have breakout boards of almost every possible type.

In my rummage through the junkbin I found an old DB25 female panel mount
connector that is connected to a colored ribbon cable. I think it's got
enough wires for me to extract the RS-232 lines from MUX and interface them
to my PC so I can use Hyperterm or some other terminal program to send ASCII
to the unit via the RS-232 interface. I was trying to figure out how to
move the pins inside the connector when I saw your message and I clicked on
the link you sent. That's *just* what I had in mind. It's pretty damn
close to magic!!!! Damn. Dave scores a home run.

Thanks again, Dave!

--
Bobby G.

[Robert Green]

I've got a MUX with a DB-25 connector on the back. The manual tells me that
the pins are arranged as follows:

01 - Alarm Input 1
02 - Alarm Input 2
03 - Alarm Input 3
04 - Alarm Input 4
05 - Alarm Input 5
06 - Alarm Input 6
07 - Alarm Input 7
08 - Alarm Input 8
09 - RS-232 RX Input
10 - RS-232 TX Input
11 - RS-232 RX Output
12 - RS-232 TX Output
13 - VCR Trigger Input
14 - Alarm Input 9
15 - Alarm Input 10
16 - Alarm Input 11
17 - Alarm Input 12
18 - Alarm Input 13
19 - Alarm Input 14
20 - Alarm Input 15
21 - Alarm Input 16
22 - Alarm Hold Input
23 - Alarm Output Common
24 - Alarm Output NC
25 - Alarm Output NO

I'm trying to hook this up to a PC using a 9 pin serial port with a DB25
adapter. I looked at the diagram for the standard RS-232 serial port
pinouts:

http://www.internet-remotecontrol.net/pccompci/rs232-cable-technology.html

At first I had hoped they used a standard configuration and chose the
location for the RS-232 lines based on where they appear on standard PC
DB-25. But pins 9-12 on a standard connector are test pins and whatnot.
The MUX pinout also uses pin 1 for an alarm channel where the standard has
it marked "ground."

Does anyone have any suggestions how to wire the MUX pinout above so that I
can communicate with it via a 9 or 25 pin PC serial port?

I'm using a 25 to 9 pin serial adapter, FWIW, because I already have a DB25
connector with a ribbon cable coming out that I can easily wire to the MUX
until my Winford Engineering breakout box arrives.

TIA!

--
Bobby G.

[Lewis Gardner]

Robert Green wrote:
> I've got a MUX with a DB-25 connector on the back. The manual tells me that
> the pins are arranged as follows:
>
> 01 - Alarm Input 1
> 02 - Alarm Input 2
> 03 - Alarm Input 3
> 04 - Alarm Input 4
> 05 - Alarm Input 5
> 06 - Alarm Input 6
> 07 - Alarm Input 7
> 08 - Alarm Input 8
> 09 - RS-232 RX Input
> 10 - RS-232 TX Input
> 11 - RS-232 RX Output
> 12 - RS-232 TX Output
> 13 - VCR Trigger Input
> 14 - Alarm Input 9
> 15 - Alarm Input 10
> 16 - Alarm Input 11
> 17 - Alarm Input 12
> 18 - Alarm Input 13
> 19 - Alarm Input 14
> 20 - Alarm Input 15
> 21 - Alarm Input 16
> 22 - Alarm Hold Input
> 23 - Alarm Output Common
> 24 - Alarm Output NC
> 25 - Alarm Output NO

> Does anyone have any suggestions how to wire the MUX pinout above so that I
> can communicate with it via a 9 or 25 pin PC serial port?

RS-232 only requires 3 wires TX RX and ground for non-hardware
handshaking communication. On a 9 pin connector those are on pins 3, 2
and 5 respectively. No standard serial cable is going to work with the
pinout you have listed above.

My guess is that on pins 9 thru 12 two of those pins are grounds and the
other two are TX and RX. The first check would be to probe those pins
with a multimeter and see if any of 9 thru 12 were connected together.
If they are those are likely the ground pin.

In an earlier post you mentioned "these MUX boxes have a RS-485 port to
connect to each other". Is it possible that pins 9 thru 12 are actually
RS-485 which uses 4 wires?

Do you have the serial protocol (baud, stop bit, parity and command
structure) for this box?

[Robert Green]

"Lewis Gardner" <lgardner@simplifiedtechnologies.com> wrote in message
news:43d688c3$1_1@news.iglou.com...
> Robert Green wrote:
> > I've got a MUX with a DB-25 connector on the back. The manual tells me
that
> > the pins are arranged as follows:
> >
> > 01 - Alarm Input 1
> > 02 - Alarm Input 2
> > 03 - Alarm Input 3
> > 04 - Alarm Input 4
> > 05 - Alarm Input 5
> > 06 - Alarm Input 6
> > 07 - Alarm Input 7
> > 08 - Alarm Input 8
> > 09 - RS-232 RX Input
> > 10 - RS-232 TX Input
> > 11 - RS-232 RX Output
> > 12 - RS-232 TX Output
> > 13 - VCR Trigger Input
> > 14 - Alarm Input 9
> > 15 - Alarm Input 10
> > 16 - Alarm Input 11
> > 17 - Alarm Input 12
> > 18 - Alarm Input 13
> > 19 - Alarm Input 14
> > 20 - Alarm Input 15
> > 21 - Alarm Input 16
> > 22 - Alarm Hold Input
> > 23 - Alarm Output Common
> > 24 - Alarm Output NC
> > 25 - Alarm Output NO
>
> > Does anyone have any suggestions how to wire the MUX pinout above so
that I
> > can communicate with it via a 9 or 25 pin PC serial port?
>
> RS-232 only requires 3 wires TX RX and ground for non-hardware
> handshaking communication. On a 9 pin connector those are on pins 3, 2
> and 5 respectively. No standard serial cable is going to work with the
> pinout you have listed above.

I didn't think so. But the bigger problem is: Which pin on the MUX is a
ground pin?

> My guess is that on pins 9 thru 12 two of those pins are grounds and the
> other two are TX and RX. The first check would be to probe those pins
> with a multimeter and see if any of 9 thru 12 were connected together.
> If they are those are likely the ground pin.

Would you test for continuity with the unit off? I'm only marginally
competent with electronics, I'm afraid. I considered looking for voltage on
the pins with the unit running, but wasn't sure which pin to use as ground.
I was leaning towards pin 23 - Alarm Output Common but it's really just a
guess. I suppose I could pop the case and try tracing the pins in question
by eye. <sigh>


> In an earlier post you mentioned "these MUX boxes have a RS-485 port to
> connect to each other". Is it possible that pins 9 thru 12 are actually
> RS-485 which uses 4 wires?

Very doubtful since it also has two jacks using what look like CAT-5
connectors labelled "RS-485 IN" and "OUT" below the DB-25 connector.
Creating a null modem cable to connect the two units seems pretty
straightforward - I think. But first, I need to access the box via RS-232
because there's no point in interconnecting them if I can't talk to them.

> Do you have the serial protocol (baud, stop bit, parity and command
> structure) for this box?

I have a list of all the ASCII and hex commands it understands. The
protocol is listed for the usual range of 1200-19600 settings. There
doesn't seem to be much more about serial networking other than a pinout of
the RS-485 connection and which pins on that connector to short to terminate
the network.

Thanks for the response!

--
Bobby G.

[Robert Green]

"Dave Houston" <nobody@whocares.com> wrote in message
news:43d676e2.398215843@nntp.fuse.net...
> "Robert Green" <ROBERT_GREEN1963@YAH00.COM> wrote:
>
> >Still looking for the breakout connector but I am sure it's here
somewhere .
>
> http://www.winfordeng.com/products/brk25.php
>
> They have breakout boards of almost every possible type.

Do I want the DIN rail or the non-DIN version? The DIN stuff looks like it
would be easier to remove and replace. Is there some other benefit?

TIA,

--
Bobby G.

[Dave Houston]

"Robert Green" <ROBERT_GREEN1963@YAH00.COM> wrote:

>Do I want the DIN rail or the non-DIN version? The DIN stuff looks like it
>would be easier to remove and replace. Is there some other benefit?

Only if you have a DIN rail. DIN rails (C shaped channels) are used here in
industrial control cabinets. In Europe they are also used in residences in
enclosures designed to hold a DIN rail.

[Lewis Gardner]

>>>09 - RS-232 RX Input
>>>10 - RS-232 TX Input
>>>11 - RS-232 RX Output
>>>12 - RS-232 TX Output

>>My guess is that on pins 9 thru 12 two of those pins are grounds and the
>>other two are TX and RX. The first check would be to probe those pins
>>with a multimeter and see if any of 9 thru 12 were connected together.
>>If they are those are likely the ground pin.
>
> Would you test for continuity with the unit off? I'm only marginally
> competent with electronics, I'm afraid. I considered looking for voltage on
> the pins with the unit running, but wasn't sure which pin to use as ground.
> I was leaning towards pin 23 - Alarm Output Common but it's really just a
> guess. I suppose I could pop the case and try tracing the pins in question
> by eye. <sigh>

For the first bit of testing I would have the unit off and check for
continuity between any two pins in the group 9 thru 12. If you find
continuity between any of those two pins they are most likely ground.

If there is no continuity between any of the pins you will need to open
the thing up and start tracing. The ground pin(s) will likely go back to
the biggest trace on the circuit board. I would stick to pins 9 thru 12
for serial communications until I was sure something else was required.

Once you have found the ground then sorting out the RX and TX is trial
and error since "TX Input" and "RX Output" are fairly meaningless. Many
serial devices will transmit a string when they power up. That is how I
have found many a TD pin and the baud, data bit, parity and stop bit
settings.

Good luck!

[Robert Green]

"Dave Houston" <nobody@whocares.com> wrote in message
news:43d6b9d9.415357812@nntp.fuse.net...
> "Robert Green" <ROBERT_GREEN1963@YAH00.COM> wrote:
>
> >Do I want the DIN rail or the non-DIN version? The DIN stuff looks like
it
> >would be easier to remove and replace. Is there some other benefit?
>
> Only if you have a DIN rail. DIN rails (C shaped channels) are used here
in
> industrial control cabinets. In Europe they are also used in residences in
> enclosures designed to hold a DIN rail.

They look to be pretty cheap on Ebay. Anything that helps keep the wiring
in line is useful. I saw an old "This Old House" today where they explored
the bowels of a very high end home. Six miles of wire of all sorts ended up
in the wire closet in the basement. It was an 80 dimmer Centralite-sort of
setup. I've never seen so much wire in a residence.

--
Bobby G.

[Robert Green]

"Lewis Gardner" <lgardner@simplifiedtechnologies.com> wrote in message
news:43d6cfa5$1_1@news.iglou.com...
>
> >>>09 - RS-232 RX Input
> >>>10 - RS-232 TX Input
> >>>11 - RS-232 RX Output
> >>>12 - RS-232 TX Output
>
> >>My guess is that on pins 9 thru 12 two of those pins are grounds and the
> >>other two are TX and RX. The first check would be to probe those pins
> >>with a multimeter and see if any of 9 thru 12 were connected together.
> >>If they are those are likely the ground pin.
> >
> > Would you test for continuity with the unit off? I'm only marginally
> > competent with electronics, I'm afraid. I considered looking for
voltage on
> > the pins with the unit running, but wasn't sure which pin to use as
ground.
> > I was leaning towards pin 23 - Alarm Output Common but it's really
just a
> > guess. I suppose I could pop the case and try tracing the pins in
question
> > by eye. <sigh>
>
> For the first bit of testing I would have the unit off and check for
> continuity between any two pins in the group 9 thru 12. If you find
> continuity between any of those two pins they are most likely ground.

That's what I will do to start.

> If there is no continuity between any of the pins you will need to open
> the thing up and start tracing. The ground pin(s) will likely go back to
> the biggest trace on the circuit board. I would stick to pins 9 thru 12
> for serial communications until I was sure something else was required.

I will visually trace the wire anyway just to be on the safe side.

> Once you have found the ground then sorting out the RX and TX is trial
> and error since "TX Input" and "RX Output" are fairly meaningless. Many
> serial devices will transmit a string when they power up. That is how I
> have found many a TD pin and the baud, data bit, parity and stop bit
> settings.

OK - that sounds like a plan. It will be a while until the breakout box
arrives anyway. Tonight I have to fire up the new PC to make sure all the
components are OK. I'm glad to see AMD finally got smart and increased the
surface area of the CPU and beefed up the mounting of enormous 5 pound
cooling fan - increased to 80mm from the puny little 40mm fans of
yesteryear. There's still a great satisfaction in cobbling all the separate
pieces together and getting it to light up and not burn up when you throw
the switch.

Thanks for your input, Lewis. I appreciate it!

--
Bobby G.

[Kurt Delaney]

"Robert Green" <ROBERT_GREEN1963@YAH00.COM> wrote >
> They look to be pretty cheap on Ebay. Anything that helps keep the wiring
> in line is useful. I saw an old "This Old House" today where they
explored
> the bowels of a very high end home. Six miles of wire of all sorts ended
up
> in the wire closet in the basement. It was an 80 dimmer Centralite-sort
of
> setup. I've never seen so much wire in a residence.

This got me thinking -- 6 miles of wire sounds like a lot, but it really is
not that much. I recently built a house and did the LV pre-wiring myself.
This is a modestly-sized home (2200 sq. ft.) single story home. I used
~1000' of bundled cable (2 cat5, 2 coax), so thats 4000 ft. right there.
Then I used an addition ~700 ft. of cat5. All of that was just for the
phone, network, and video outlets. Then I ran a ton more 22/4 wire for
security pre-wire -- home-run to each window, door, and locations for motion
(indoor and outdoor), glass break, thermostats, smoke, heat and CO
detectors, as well as keypads, sounders, etc. I figure I ran over 2000 ft.
of that wire.

So totaled up, I have about a mile and a half of wire (w/o counting lighting
wire), and my home is nowhere near a "very high end home". When I finish
off the basement (another 2100 sq. ft.) I will have run over 2 1/2 miles of
LV wire.

Kurt

[Robert Green]

"Kurt Delaney" <kurt_dot_delaney@rm_this_hp.com> wrote in message

<stuff snipped>

> This got me thinking -- 6 miles of wire sounds like a lot, but it really
is
> not that much.

These guys were using structured cable with 2 RG6QS and 2 CAT-5 cables in
every jacket and I don't think they were counting the separate cables in the
length total! This home's automation center looked like a nuke sub's
missile room. They even had a giant power conditioner with a coil that
looked to be over a foot in diameter. It was very impressive. I'm only
sorry I didn't tape it.

One thing's for sure. Modern home automation = boatloads of wire!

--
Bobby G.

[Solo Rider]

"Robert Green" <ROBERT_GREEN1963@YAH00.COM> wrote in message
news:D8ydnTHSa6IWeEveRVn-gg@rcn.net...
> "Kurt Delaney" <kurt_dot_delaney@rm_this_hp.com> wrote in message
>
> <stuff snipped>
>
>> This got me thinking -- 6 miles of wire sounds like a lot, but it really
> is
>> not that much.
>
> These guys were using structured cable with 2 RG6QS and 2 CAT-5 cables in
> every jacket and I don't think they were counting the separate cables in
> the
> length total! This home's automation center looked like a nuke sub's
> missile room. They even had a giant power conditioner with a coil that
> looked to be over a foot in diameter. It was very impressive. I'm only
> sorry I didn't tape it.
>
> One thing's for sure. Modern home automation = boatloads of wire!

We area starting to plan our next home. LV equipment and wire are a
distinct line item and the cost allocated to it is climbing rapidly