video question on IBM 5150 computer

~A_Sammy wrote:
 > Hi,
 > I got the following email tonight from a buddy:
 >
 >
   >>>You may recall that I have an IBM 5150--the 1st production PC made
 >
 > (1981)--that I'm going to sell since it's collectible. Well, I finally got
 > around to looking at it, and it powers up, but its video port won't work
 > with current monitor plugs. Since the ports aren't labeled, I'm guessing
 > that the video port is the one that's shaped and sized like the current
 > ones. This has 9 pinholes, 5 on one row, 4 on the other. Current monitor
 > plugs seem to have 3 rows of pins. Do you have a monitor that could work?<<
 >
 > It sounds to me that he is describing a serial port, but a 1981 IBM is way
 > before my time.
 >
 > Can anybody tell me what the score is on video for an old box like that?
 >
 > Thanks,
 >
 > Sammy
 >
 >
 >
 >
  I believe this computer used either Monochrome or CGA cards for the
video. That is why your VGA connector (used on newer computers) is not
present on the old one.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: video question on IBM 5150 computer 

Gary Tait <classicsat.DeleteThis@yahoo.cominvalid> wrote:
 > If the card with the 9 pin female has a parallell port, it is a
 > Monochrome card, if it has an RCA jack or two, it will be CGA card.

There are also adapters out there that will convert a CGA signal to VGA;
the Commodore 128 used a CGA-compatible signal, and I've got one such
adapter for connecting a VGA monitor to my 128.

AFAICT, you could also make one by buying a 9-pin male connector and a
15-pin female; and at worst, you might need a resistor or two to get the
voltages right.

--
Nate Edel http://www.nkedel.com/

"I do have a cause though. It is obscenity. I'm for it." - Tom Lehrer<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: video question on IBM 5150 computer 

On Wed, 28 Jan 2004 03:28:57 -0800, archmage.DeleteThis@sfchat.org (Nate Edel)
wrote:

 >Gary Tait <classicsat.DeleteThis@yahoo.cominvalid> wrote:
  >> If the card with the 9 pin female has a parallell port, it is a
  >> Monochrome card, if it has an RCA jack or two, it will be CGA card.
 >
 >There are also adapters out there that will convert a CGA signal to VGA;
 >the Commodore 128 used a CGA-compatible signal, and I've got one such
 >adapter for connecting a VGA monitor to my 128.
 >
 >AFAICT, you could also make one by buying a 9-pin male connector and a
 >15-pin female; and at worst, you might need a resistor or two to get the
 >voltages right.

Not easily. The sync rates are different, unless you have a good
multisync monitor.<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: video question on IBM 5150 computer 

Gary Tait <classicsat.DeleteThis@yahoo.cominvalid> wrote in message news:<oa4g10ls2otqv7c0p4vvcmpt3pkl8ijof2.DeleteThis@4ax.com>...
 > On Wed, 28 Jan 2004 03:28:57 -0800, archmage.DeleteThis@sfchat.org (Nate Edel)
 > wrote:
 >
  > >Gary Tait <classicsat.DeleteThis@yahoo.cominvalid> wrote:
   > >> If the card with the 9 pin female has a parallell port, it is a
   > >> Monochrome card, if it has an RCA jack or two, it will be CGA card.
  > >
  > >There are also adapters out there that will convert a CGA signal to VGA;
  > >the Commodore 128 used a CGA-compatible signal, and I've got one such
  > >adapter for connecting a VGA monitor to my 128.
  > >
  > >AFAICT, you could also make one by buying a 9-pin male connector and a
  > >15-pin female; and at worst, you might need a resistor or two to get the
  > >voltages right.
 >
 > Not easily. The sync rates are different, unless you have a good
 > multisync monitor.

Nothing like the same question posted to two newsgroups separately.

I gather the original CGA card had a header for connecting to an
RF modulator for feeding a tv set. So one could go that route,
or use the video signal that must be there to feed an NTSC monitor
of some sort (like the monitor sitting around from the Commodore
64 days), a tv set with composite video input, or a VCR that will
act like an RF modulator that in turn feeds a tv set.

As I said in the other newsgroup, later CGA cards (which were nice
and short and did have a printer port on them) had either a two
pin header for a phono jack that outputted composite video, or
had a phono jack right on the board. I imagine there might have
even been boards with a phono connector on the metal strip at
the back. One can use this point to easily connect the card
to the NTSC monitor, which are likely to be more available than
an RGBi monitor that the nine pin connector is intended for.

As I also said in the other newsgroup, just because the computer
is an original IBM, there is nothing to guarantee that the video
card was not changed. If it was bought early, it might have come
with the monochrome card, and then changed when those smaller
CGA cards came along. Or for that matter, someone could have
changed to an EGA card when they came along; they too have a nine pin
"DB" connector.

Michael<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: video question on IBM 5150 computer 

On 29 Jan 2004 09:25:19 -0800, blackm00 DeleteThis @cam.org (Michael Black) wrote:

 >Gary Tait <classicsat DeleteThis @yahoo.cominvalid> wrote in message news:<oa4g10ls2otqv7c0p4vvcmpt3pkl8ijof2 DeleteThis @4ax.com>...
  >> On Wed, 28 Jan 2004 03:28:57 -0800, archmage DeleteThis @sfchat.org (Nate Edel)
  >> wrote:
  >>
   >> >Gary Tait <classicsat DeleteThis @yahoo.cominvalid> wrote:
   >> >> If the card with the 9 pin female has a parallell port, it is a
   >> >> Monochrome card, if it has an RCA jack or two, it will be CGA card.
   >> >
   >> >There are also adapters out there that will convert a CGA signal to VGA;
   >> >the Commodore 128 used a CGA-compatible signal, and I've got one such
   >> >adapter for connecting a VGA monitor to my 128.
   >> >
   >> >AFAICT, you could also make one by buying a 9-pin male connector and a
   >> >15-pin female; and at worst, you might need a resistor or two to get the
   >> >voltages right.
  >>
  >> Not easily. The sync rates are different, unless you have a good
  >> multisync monitor.
 >
 >Nothing like the same question posted to two newsgroups separately.
 >
 >I gather the original CGA card had a header for connecting to an
 >RF modulator for feeding a tv set. So one could go that route,
 >or use the video signal that must be there to feed an NTSC monitor
 >of some sort (like the monitor sitting around from the Commodore
 >64 days), a tv set with composite video input, or a VCR that will
 >act like an RF modulator that in turn feeds a tv set.
 >

I might have an original IBM card that has an RCA out. I have a clone
card that hast two RCA jacks, one colour, one monochrome (which I used
great on a monochrome composite video CRT). They have a header that
may be for a lite pen.

 >As I said in the other newsgroup, later CGA cards (which were nice
 >and short and did have a printer port on them) had either a two

Some where dual CGA/Monochrome (hercules graphics standard). I have
one with a toggle switch to switch between the modes. I don't think
there were any short IBM CGA/Monochrome cards, they were all
aftermarket (of the ones I have).

 >pin header for a phono jack that outputted composite video, or
 >had a phono jack right on the board. I imagine there might have
 >even been boards with a phono connector on the metal strip at
 >the back. One can use this point to easily connect the card
 >to the NTSC monitor, which are likely to be more available than
 >an RGBi monitor that the nine pin connector is intended for.
 >
 >As I also said in the other newsgroup, just because the computer
 >is an original IBM, there is nothing to guarantee that the video
 >card was not changed. If it was bought early, it might have come
 >with the monochrome card, and then changed when those smaller
 >CGA cards came along. Or for that matter, someone could have
 >changed to an EGA card when they came along; they too have a nine pin
 >"DB" connector.
 >

Actually, the spec for that connector would be DE-9, E specifying the
size of the shell (B sized shell being what is used for 25 pin
parallel and serial ports)
 > Michael<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: video question on IBM 5150 computer 

Thanks for the replys. I double posted the question because I have found
there are different "pools" of expertise in each.
I found, in my parts bin a couple days after the posts, an ancient ISA video
card with both a 9 pin and a VGA output on it. It had a bunch of dip
switches on it which I left alone.
It worked! Just plugged it in, fired up the PC, and viola! video. Didn't
know what to do with the interface though. It was something I had seen long
ago on a Tandy. It had a list across the bottom of commands, like load,
run, toff, ton, etc. This machine belongs to a friend who only wanted to
know if it worked or not.
Thanks again,
Sammy
 >> Stay informed about: video question on IBM 5150 computer 

On Sun, 8 Feb 2004 20:42:14 -0500, "~A_Sammy" <bogus.TakeThisOut@nowhere.net> wrote:

 >Thanks for the replys. I double posted the question because I have found
 >there are different "pools" of expertise in each.
 >I found, in my parts bin a couple days after the posts, an ancient ISA video
 >card with both a 9 pin and a VGA output on it. It had a bunch of dip
 >switches on it which I left alone.
 >It worked! Just plugged it in, fired up the PC, and viola! video. Didn't
 >know what to do with the interface though. It was something I had seen long
 >ago on a Tandy. It had a list across the bottom of commands, like load,
 >run, toff, ton, etc. This machine belongs to a friend who only wanted to
 >know if it worked or not.
 >Thanks again,
 >Sammy
 >
What you are seeing is the built in Basic interpreter that IBM had in ROM.
If you don't boot off of a disk, you get this basic, and can key in and run
programs and save them to cassette tape

JT<!-- ~MESSAGE_AFTER~ -->
 >> Stay informed about: video question on IBM 5150 computer