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IBM MCA Card Infowindow VGA Control

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RadRacer203

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Just dug this card out, and I'm planning on selling it but I'm not really sure what it is. I know it's a video card, and it says VGA but it has a db9 port and an RCA port, I'm assuming for composite out. Anyone know what the capabilities are? The part number on it is 83X9228
 
RadRacer203 said:
Just dug this card out, and I'm planning on selling it but I'm not really sure what it is. I know it's a video card, and it says VGA but it has a db9 port and an RCA port, I'm assuming for composite out. Anyone know what the capabilities are? The part number on it is 83X9228
Click to expand...

Photo plz.
 
It's for something similar to the BBC Domesday project. Computers weren't powerful enough and didn't have enough hard drive space to store video or large quantities of images back then, so they stored all the video and photos on a LaserDisc and then used the computer to control the LaserDisc player, whose video output would be overlayed with that of the computer's.

 
I have an Infowindow 4055 display, but no software, or control card. It came from an XT about 25 years ago. I wish I was able to grab the entire system because it might have had the requisite card. In fact, it came from an entire lab of such systems. But this was just one of the spare parts, which is how I got it.

I do not have MCA, so if anyone has the ISA version and software, I would be interested. The other thing is I believe it will require an EGA card. I've debated buying one, but I don't think it's worth it just for EGA. I hooked it up to a CGA card on a 5150, and it's great since it supports both RGB and composite. Also, not sure what I could hook the speakers up to on the 5150, but it makes a nice all in one system.

I would be interested in running the control card with the program interface, because I believe it can drive the touch screen, on screen display text, and speech synthesis supported by the monitor.

Note there is an Infowindow II or some kind of terminal computer version. That is not the same thing as I have, but unfortunately any search turns up that instead and makes searching for the program and card fairly hard. I did see the software pop up on ebay a few weeks ago.
 
the3dfxdude said:
I have an Infowindow 4055 display, but no software, or control card. It came from an XT about 25 years ago. I wish I was able to grab the entire system because it might have had the requisite card. In fact, it came from an entire lab of such systems. But this was just one of the spare parts, which is how I got it.

I do not have MCA, so if anyone has the ISA version and software, I would be interested. The other thing is I believe it will require an EGA card. I've debated buying one, but I don't think it's worth it just for EGA. I hooked it up to a CGA card on a 5150, and it's great since it supports both RGB and composite. Also, not sure what I could hook the speakers up to on the 5150, but it makes a nice all in one system.

I would be interested in running the control card with the program interface, because I believe it can drive the touch screen, on screen display text, and speech synthesis supported by the monitor.

Note there is an Infowindow II or some kind of terminal computer version. That is not the same thing as I have, but unfortunately any search turns up that instead and makes searching for the program and card fairly hard. I did see the software pop up on ebay a few weeks ago.
Click to expand...

If you want this card, it's for sale, and cheap. Maybe you can find a PS/2 to use it in
 
RadRacer203 said:
If you want this card, it's for sale, and cheap. Maybe you can find a PS/2 to use it in
Click to expand...

I have no interest in a PS/2 at the moment.

Actually, reviewing the Infowindow link again, and you saying you have the MCA VGA version, kind of makes me wonder again what the deal is. The RCA port is for graphics sync, not composite. But I'm not sure how it would support VGA on the 4055. I'm pretty sure the XT it came from was either CGA or EGA based. The monitor sure didn't take the multisync mode on a CGA card I had. But it is clearly CGA TTL compatible. I think there must be a later model for the PS/2 MCA adapter.
 
RadRacer203 said:
Well this card has a 9 pin vga output, maybe the monitor is compatible with that standard
Click to expand...

So after some work, I've determined that the card you have is almost certainly NOT a VGA card. The monitor is intended to receive an EGA signal, and accepts the EGA frequencies vsync/hsync through the 9pin port according to the documentation. There was no later model for this monitor specifically made for the PS/2 that gave it VGA functionality. (*the InfoWindow was discontinued not long after the MCA refresh and InfoWindow II is not related at all)

Anyway, I think it was just IBM marketing at play here. What this card is really is an update of their offering with MCA for PS/2 compatibility. It took the original IBM EGA + Memory Expansion + EGA Jumper card and put it into a single board. Although since it is for a special monitor, it might not be all that useful as an EGA by itself, and really I think the card is going to lack any purpose without the complete system. Indeed, if someone comes across one of these again, they should not part it out as if it's just another IBM PC/XT or PS2.

Anyhow the reason I decided to reply again here is since I have an IBM PC, with a standard EGA card, I need the EGA jumper card for the sync signal (what the RCA port is for). Could you take a high resolution photo of your InfoWindow VGA card, front and back? I think the purpose of the jumper card was to use the sync signal to activate IRQ 2. I hooked a scope to the sync signal from the monitor, and it appeared that it has some sort of combined horizontal and vertical pulse, I'm guessing from the CRT? If I can figure the signal path from your card, then I could probably recreate the jumper card for its intended purpose.
 
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the3dfxdude said:
So after some work, I've determined that the card you have is almost certainly NOT a VGA card. The monitor is intended to receive an EGA signal, and accepts the EGA frequencies vsync/hsync through the 9pin port according to the documentation. There was no later model for this monitor specifically made for the PS/2 that gave it VGA functionality. (*the InfoWindow was discontinued not long after the MCA refresh and InfoWindow II is not related at all)

Anyway, I think it was just IBM marketing at play here. What this card is really is an update of their offering with MCA for PS/2 compatibility. It took the original IBM EGA + Memory Expansion + EGA Jumper card and put it into a single board. Although since it is for a special monitor, it might not be all that useful as an EGA by itself, and really I think the card is going to lack any purpose without the complete system. Indeed, if someone comes across one of these again, they should not part it out as if it's just another IBM PC/XT or PS2.

Anyhow the reason I decided to reply again here is since I have an IBM PC, with a standard EGA card, I need the EGA jumper card for the sync signal (what the RCA port is for). Could you take a high resolution photo of your InfoWindow VGA card, front and back? I think the purpose of the jumper card was to use the sync signal to activate IRQ 2. I hooked a scope to the sync signal from the monitor, and it appeared that it has some sort of combined horizontal and vertical pulse, I'm guessing from the CRT? If I can figure the signal path from your card, then I could probably recreate the jumper card for its intended purpose.
Click to expand...

There's an old VCFED thread about the jumper card: http://www.vcfed.org/forum/showthread.php?28770-IBM-EGA-Feature-Connector-Card

From the photos in that thread I was able to reverse engineer the jumper card:

Capture.PNG

There's a test point in the upper corner of the jumper card. You're supposed to run that over to the IBM GPIB card (which is apparently needed to run the laserdisc player) which has an IRQ jumper block. The jumper wire goes to either IRQ2, IRQ3, or IRQ4.

What does this whole thing do? Two things: First, it generates a VSYNC signal that is delayed by two horizontal lines. When a feature control bit is turned on, this signal triggers the selected interrupt line. Second, it ties the RCA jack J1 to the EXT_OSC input. There is a register that selects the EGA pixel clock from either 16.257MHz (on the card), 14.318MHz (on the planar), or the EXT_OSC input. Presumably the 4055 provides this as part of the genlock circuit for video overlay purposes.

Hope this helps.
 
ejs said:
There's an old VCFED thread about the jumper card: http://www.vcfed.org/forum/showthread.php?28770-IBM-EGA-Feature-Connector-Card

From the photos in that thread I was able to reverse engineer the jumper card:

View attachment 60851

There's a test point in the upper corner of the jumper card. You're supposed to run that over to the IBM GPIB card (which is apparently needed to run the laserdisc player) which has an IRQ jumper block. The jumper wire goes to either IRQ2, IRQ3, or IRQ4.

What does this whole thing do? Two things: First, it generates a VSYNC signal that is delayed by two horizontal lines. When a feature control bit is turned on, this signal triggers the selected interrupt line. Second, it ties the RCA jack J1 to the EXT_OSC input. There is a register that selects the EGA pixel clock from either 16.257MHz (on the card), 14.318MHz (on the planar), or the EXT_OSC input. Presumably the 4055 provides this as part of the genlock circuit for video overlay purposes.

Hope this helps.
Click to expand...

Yes. Thank you.

I drew up a Kicad schematic a few months back based on that image. I figured I might eventually ask someone to double check the drawing but since you have shared yours, I did just now. Looks like we are in agreement there.

Thanks for the info on the EGA clock register. I will be watching that when I issues commands to the system.

If I wasn't clear about this before, the IBM diagnostics disk requires the jumper card installed. It is likely triggering the feature control bit and watching for the interrupt at startup. It will not continue without the card. I don't think it should need the clock to perform the other functions, but when programming the thing using the IBM library, you issue a start command to the display unit, to be able to drive the functions on the display. It is likely there is a negotiation with the jumper card which eventually may lead to switching from the internal oscillator to the external oscillator. Hopefully this works with my clone EGA card. I guess that explains why it calls the sync a dot clock in some places in the documentation.

The monitor uses GPIB to communicate with the computer.

I'll be gathering the parts and checking how this works and integrating in time. If there is something about operating it that I can't figure out, I'll open a new thread.
 
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