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Null modem serial cable

 
 
Andy1973
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      04-16-2006, 09:06 AM
I have bought a new computer with a 9-pin female socket enabling transfer of
files and more importantly settings (eg modem setup) from another computer.
My old computer is an Advent 3604. My problem is that I don't know which
socket on the Advent might be usable for a null modem serial cable. The
cable has to connect to a serial port, but I'm not sure which ports are
serial. The Advent printer port, which is serial (I think), has a 15 pin
connection, but the cables only come in 9-pin or 15-pin configurations. Any
advice? TIA


 
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Roger Mills
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      04-16-2006, 09:37 AM
In an earlier contribution to this discussion,
Andy1973 <(E-Mail Removed)> wrote:

> I have bought a new computer with a 9-pin female socket enabling
> transfer of files and more importantly settings (eg modem setup) from
> another computer. My old computer is an Advent 3604. My problem is
> that I don't know which socket on the Advent might be usable for a
> null modem serial cable. The cable has to connect to a serial port,
> but I'm not sure which ports are serial. The Advent printer port,
> which is serial (I think), has a 15 pin connection, but the cables
> only come in 9-pin or 15-pin configurations. Any advice? TIA


Computer serial ports are invariably *male* (i.e. configured as terminals
rather than datasets) - either as a 9-pin or 25-pin D-connector.

If you have a 15-pin connector, it's probably a game/joystick port which is
not what you want. The printer port on most computers takes the form of a
25-pin *female* socket - but is actally parallel rather than serial.

A null modem cable needs to have female connectors both ends to plug into
the computers' male sockets. The connections will be crossed over so that
the outputs from one computer go to the inputs of the other one, and vice
versa.
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Roger
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PLEASE REPLY TO NEWSGROUP!


 
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Mark McIntyre
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      04-16-2006, 10:04 AM
On Sun, 16 Apr 2006 10:06:41 +0100, in uk.telecom.broadband ,
"Andy1973" <(E-Mail Removed)> wrote:

>I have bought a new computer with a 9-pin female socket enabling transfer of
>files and more importantly settings (eg modem setup) from another computer.
>My old computer is an Advent 3604. My problem is that I don't know which
>socket on the Advent might be usable for a null modem serial cable. The
>cable has to connect to a serial port, but I'm not sure which ports are
>serial.


Normally, serial ports come in 9 or 25-pin varieties. Most PCs built
in the last decade have the 9-pin variety, but you can still find the
occasional 25-pin variety. Serial ports on PCs are always female.

>The Advent printer port, which is serial (I think), has a 15 pin
>connection, but the cables only come in 9-pin or 15-pin configurations.


Printer ports are not serial ports, as a rule. 15-pin is also pretty
odd - printer ports are normally 25-way male.

Don't you have the original instruction booklet for the Advent?
Mark McIntyre
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Bob Eager
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      04-16-2006, 10:21 AM
On Sun, 16 Apr 2006 10:04:44 UTC, Mark McIntyre
<(E-Mail Removed)> wrote:

> Normally, serial ports come in 9 or 25-pin varieties. Most PCs built
> in the last decade have the 9-pin variety, but you can still find the
> occasional 25-pin variety. Serial ports on PCs are always female.
>
> >The Advent printer port, which is serial (I think), has a 15 pin
> >connection, but the cables only come in 9-pin or 15-pin configurations.

>
> Printer ports are not serial ports, as a rule. 15-pin is also pretty
> odd - printer ports are normally 25-way male.


For the avoidance of confusion here...

Serial - physical port is male, cable end is thus female (9 pin or 25
pin)
Parallel - physical port is female, cable end is thus male (25 pin)
--
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to give concise answers, express reasoned argument or opinion.
Usually accompanied by silly noises and gestures - incurable, early
euthanasia recommended. ]
 
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Roger Mills
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      04-16-2006, 10:23 AM
In an earlier contribution to this discussion,
Mark McIntyre <(E-Mail Removed)> wrote:

>
> Normally, serial ports come in 9 or 25-pin varieties. Most PCs built
> in the last decade have the 9-pin variety, but you can still find the
> occasional 25-pin variety. Serial ports on PCs are always female.


No they're not, they're MALE. You *do* know the difference, don't you?!

>
> Printer ports are not serial ports, as a rule. 15-pin is also pretty
> odd - printer ports are normally 25-way male.
>

WRONG again - they're FEMALE. Have a look at the back of your PC!

A serial cable needs to have a female plug to connect to the male port.
Similarly, a parallel cable needs a male plug to connect to the female port.
--
Cheers,
Roger
______
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monitored.. Messages sent to it may not be read for several weeks.
PLEASE REPLY TO NEWSGROUP!


 
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Ivor Jones
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      04-16-2006, 06:00 PM


"Roger Mills" <(E-Mail Removed)> wrote in message
news:(E-Mail Removed)
> In an earlier contribution to this discussion,
> Mark McIntyre <(E-Mail Removed)> wrote:
>
> >
> > Normally, serial ports come in 9 or 25-pin varieties.
> > Most PCs built in the last decade have the 9-pin
> > variety, but you can still find the occasional 25-pin
> > variety. Serial ports on PCs are always female.

>
> No they're not, they're MALE. You *do* know the
> difference, don't you?!
> >
> > Printer ports are not serial ports, as a rule. 15-pin
> > is also pretty odd - printer ports are normally 25-way
> > male.

> WRONG again - they're FEMALE. Have a look at the back of
> your PC!
> A serial cable needs to have a female plug to connect to
> the male port. Similarly, a parallel cable needs a male
> plug to connect to the female port.


While we're on the subject, anyone know of a *reliable* USB to serial
converter..? My new laptop doesn't have any serial ports and I have
numerous devices requiring one. The one I bought from Maplins (best part
of fifteen bloody quid) got me the dreaded blue screen of death when I
loaded the driver.

Ivor


 
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Dave Stanton
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      04-16-2006, 06:27 PM

> While we're on the subject, anyone know of a *reliable* USB to serial
> converter..? My new laptop doesn't have any serial ports and I have
> numerous devices requiring one. The one I bought from Maplins (best part
> of fifteen bloody quid) got me the dreaded blue screen of death when I
> loaded the driver.
>
> Ivor


You also have to be aware that some don't give the right levels or have
all the required lines for all applications. Bit of a bodge really.

Dave

 
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David G. Bell
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      04-16-2006, 06:43 PM
On Sunday, in article <(E-Mail Removed)>
(E-Mail Removed)lid "Ivor Jones" wrote:

> "Roger Mills" <(E-Mail Removed)> wrote in message
> news:(E-Mail Removed)
> > In an earlier contribution to this discussion,
> > Mark McIntyre <(E-Mail Removed)> wrote:
> >
> > >
> > > Normally, serial ports come in 9 or 25-pin varieties.
> > > Most PCs built in the last decade have the 9-pin
> > > variety, but you can still find the occasional 25-pin
> > > variety. Serial ports on PCs are always female.

> >
> > No they're not, they're MALE. You *do* know the
> > difference, don't you?!
> > >
> > > Printer ports are not serial ports, as a rule. 15-pin
> > > is also pretty odd - printer ports are normally 25-way
> > > male.

> > WRONG again - they're FEMALE. Have a look at the back of
> > your PC!
> > A serial cable needs to have a female plug to connect to
> > the male port. Similarly, a parallel cable needs a male
> > plug to connect to the female port.

>
> While we're on the subject, anyone know of a *reliable* USB to serial
> converter..? My new laptop doesn't have any serial ports and I have
> numerous devices requiring one. The one I bought from Maplins (best part
> of fifteen bloody quid) got me the dreaded blue screen of death when I
> loaded the driver.


Funny, the one I bought from Maplins works fine.

But it surely depends on which precise model of computer and converter
you have.

So show off a little, tell us what your latest flash toy is.

--
David G. Bell -- SF Fan, Filker, and Punslinger.

"I am Number Two," said Penfold. "You are Number Six."
 
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Alan J. Flavell
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      04-16-2006, 07:07 PM
On Sun, 16 Apr 2006, Ivor Jones wrote:

> While we're on the subject, anyone know of a *reliable* USB to
> serial converter..?


We're using the Targus PA088E

> My new laptop doesn't have any serial ports and I have numerous
> devices requiring one. The one I bought from Maplins (best part of
> fifteen bloody quid) got me the dreaded blue screen of death when I
> loaded the driver.


Well, if you're unhappy with fifteen quid, then you'll be quite
depressed with the price of this product. On the other hand, it's
worked fine for us (talking, via a null modem cable, to the async
serial management port on a selection of different networking boxes).

Plugged into Linux, it worked right out of the box, and talks just
fine from e.g ckermit software, after setting the appropriate serial
device name. The necessary clues are right there in /var/log/messages
as one plugs it in:

> Mar 10 22:49:05 localhost kernel: usbserial.c: USB Serial support
> registered for Magic Control Technology USB-RS232
> Mar 10 22:49:05 localhost kernel: usbserial.c: Magic Control Technology
> USB-RS232 converter detected
> Mar 10 22:49:05 localhost kernel: usbserial.c: Magic Control Technology
> USB-RS232 converter now attached to ttyUSB0 (or usb/tts/0 for devfs)


Indeed the device appears as /dev/ttyUSB0


OTOH, the instructions for Windoze were emphatic that one had to
install the supplied software and reboot, before plugging the thing
in. So that's what I did - I've no idea what would have happened
otherwise. After that, all I can say is that it does work on Win/XP
(as COM4).

By the way, this inscrutable statement on the spec:

Connector(s) (Other Side): 1 x 9 pin D-Sub (DB-9) - female

is probably best disregarded. "Other Side" of what??? The device
has, as one would expect, a 9-pin *male* connector, just like a
computer's regular serial port would have.

 
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David Rance
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      04-16-2006, 07:39 PM
On Sun, 16 Apr 2006 Ivor Jones wrote:

>While we're on the subject, anyone know of a *reliable* USB to serial
>converter..? My new laptop doesn't have any serial ports and I have
>numerous devices requiring one. The one I bought from Maplins (best part
>of fifteen bloody quid) got me the dreaded blue screen of death when I
>loaded the driver.


I bought one from Maplin's years ago and it was useless. Then I bought a
Belkin one and never had any problems with it.

David

--
David Rance (E-Mail Removed) http://www.mesnil.demon.co.uk
Fido Address: 2:252/110 writing from Caversham, Reading, UK

 
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