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per
May 15th, 2010, 02:09 PM
Sorry for double-posting this, but I figured the title in the first version of this thread was misleading.

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I have gotten the IBM EGA card I just aquired, and I have now run the advanced diagnostics v2.25 on it to see if it's malfunctioning.

One problem is that on some of the tests, I don't know how it actually is supposed to look like. This is a problem, since it didn't look quite usual on the 640x350 test. What I find odd is that the rightmost square is flashing, but not on the part overlapping the middle square. I am sure I have set all the jumpers corrctly, and I do use a real 5151 with it.

Is anybody able to verify if this is correct behavour for this graphics mode?

Floppies_only
May 15th, 2010, 09:44 PM
Sorry for double-posting this, but I figured the title in the first version of this thread was misleading.

-----

I have gotten the IBM EGA card I just aquired, and I have now run the advanced diagnostics v2.25 on it to see if it's malfunctioning.

One problem is that on some of the tests, I don't know how it actually is supposed to look like. This is a problem, since it didn't look quite usual on the 640x350 test. What I find odd is that the rightmost square is flashing, but not on the part overlapping the middle square. I am sure I have set all the jumpers corrctly, and I do use a real 5151 with it.

Is anybody able to verify if this is correct behavour for this graphics mode?

I'm confused by the way you set up your question. You didn't say what kind of monitor the EGA card was set to display on but you did say you were using a 5151 monitor and the 640X350 mode. The EGA card can drive either a 5151, 5153, or 5154 monitor if it's jumpers are set correctly. But the only one of those that can display 640X350 resolution is the 5154, enhanced color display. You can get graphics on a 5151 if you are using a Hercules card, but the resolution is something like 720X348. Perhaps the EGA card can do that, too. I don't know.

How about using regular programs with the setup and seeing if things look correct?

Sean

per
May 16th, 2010, 06:52 AM
I'm confused by the way you set up your question. You didn't say what kind of monitor the EGA card was set to display on but you did say you were using a 5151 monitor and the 640X350 mode. The EGA card can drive either a 5151, 5153, or 5154 monitor if it's jumpers are set correctly. But the only one of those that can display 640X350 resolution is the 5154, enhanced color display. You can get graphics on a 5151 if you are using a Hercules card, but the resolution is something like 720X348. Perhaps the EGA card can do that, too. I don't know.

How about using regular programs with the setup and seeing if things look correct?

Sean

I am using the IBM 5151 monochrome monitor with it, and the jumpers are set correctly. Textmode works perfectly, so it's nothing wrong with the output.

Whereas the IBM EGA can display 640x350 on a mono monitor or not (and how it should appear if supported) must be stated in the technical referance, however I don't have it and that's why I'm asking this question. I know at least some members of this forum got it.

mikey99
May 16th, 2010, 12:55 PM
I have an EGA card with 5154 EGA Display. I booted the XT 2.25 Diagnostics diskette and ran the tests.

Are you referring to Test 6) Hi-res graphics on the menu ?
On this test it switches to 640x350 mode....I see all the colors and none are blinking.

Oddly, Test 12) Sync test doesn't seem to work correctly , the display goes out of sync so I'm not sure
what this test really does. The display works fine and I've never seen any issues with corrupted
graphics or anything out of the ordinary.

per
May 16th, 2010, 01:28 PM
I have an EGA card with 5154 EGA Display. I booted the XT 2.25 Diagnostics diskette and ran the tests.

Are you referring to Test 6) Hi-res graphics on the menu ?
On this test it switches to 640x350 mode....I see all the colors and none are blinking.

Oddly, Test 12) Sync test doesn't seem to work correctly , the display goes out of sync so I'm not sure
what this test really does. The display works fine and I've never seen any issues with corrupted
graphics or anything out of the ordinary.

I don't know how it would look with my card on an 5154, but I think that's quite differerent render cirquits since the sync-rates for the 5151 is different, and the 5151 only has 2-bit (theoretically; practically only logarithm-of-3-in-base-2-bit) color depth. When a 5151 is used with the EGA (and the card is correctly jumpered), it actually shows up as test number 4.

The sync tests are not meant to work with a monitor. when doing the sync tests, you unplug the monitor an put a multimeter on two pins of the display connector before running the test. That's why they're below the "run all of the above tests" option.

Floppies_only
May 16th, 2010, 06:28 PM
Per,

O.K., I checked Scott Meuller's "Upgrading and Repairing PCs" and it says that the EGA card can't do graphics on a 5151 monitor. The only graphics modes are for the CGA and EGA monitors: up to 640 x 200 and 640 x 350 pixels, respectively. If you are driving a 5151 monitor you get 720 x 350 pixels, but in text mode only, not "all points addressable".

I was wondering about those advanced diagnostics version 2.25 that you are using. Is that what comes with the Hardware Maintenence and Service manual?

Thanks,
Sean

per
May 17th, 2010, 02:48 AM
Per,

O.K., I checked Scott Meuller's "Upgrading and Repairing PCs" and it says that the EGA card can't do graphics on a 5151 monitor. The only graphics modes are for the CGA and EGA monitors: up to 640 x 200 and 640 x 350 pixels, respectively. If you are driving a 5151 monitor you get 720 x 350 pixels, but in text mode only, not "all points addressable".

I was wondering about those advanced diagnostics version 2.25 that you are using. Is that what comes with the Hardware Maintenence and Service manual?

Thanks,
Sean

It's the final version of the PC/XT diagnostics from IBM. The diagnostics program is aware of the card being used with a 5151, firstly because it stares it on screen, and that most of the graphics mode tests aren't present. However, for some reason the 640 x 350 pixel mode test remains. Perhaps it's a tweaked texmode nobody really used (like the CGA 160*100 pixel 16-color mode)?

I don't think the monochrome 640x350 pixel graphics mode is unsupported on the real IBM EGA (it's even one of the installation options for Windows 1.x), because when the test is run; graphics actually happen to apear on the screen with perfect sync. What I'm unsure about is just if it appears correctly or not (the blinking issue).

southbird
May 17th, 2010, 06:11 PM
Yeah, there definitely is some kind of 640x350 graphics. I ran SimCity with an EGA card geared into an amber monochrome monitor of some sort once. I'd be surprised (and not surprised I guess) if it was some kind of hyper text mode...

mikey99
May 18th, 2010, 11:23 AM
The sync tests are not meant to work with a monitor. when doing the sync tests, you unplug the monitor an put a multimeter on two pins of the display connector before running the test. That's why they're below the "run all of the above tests" option.

Thanks, thats good to know. At first I thought there might be a problem with my 5154 which would have been bad news
considering I just spent a few hours replacing all capacitors in the power supply.