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IBM EGA card DIP switch settings

dongfeng

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Joined
Nov 16, 2003
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Does anybody have the DIP switch settings for the IBM EGA card? The 5154 EGA display on my AT is broken, and I would like to replace it (temporally) with a 5153 CGA display.
 
Switch settings for original IBM EGA board (and most clone EGA boards).

Code:
      ┌─────────┐
      │ 1 2 3 4 │
┌─────┼─────────┤   NOTE:  On some boards a jumper needs to be changed for
│ MON │ 0 0 1 0 │          CGA mode (controls pin 2 on DB9).
│ CGA │ 0 0 0 1 │
│ EGA │ 0 1 1 0 │
└─────┴─────────┘
 
You know, Google would have answered this question perfectly well. DIP switch settings for EGA cards are not a state secret.
 
I always look on Google first. I couldn't find the IBM EGA card switch setting in either Google, Google's Newsgroup archive, Total Hardware 99, nor Upgrading and Repairing PC's (6th Edition). Hence I asked here ;)

I now know however, the EGA card switch settings are somewhat generic between cards. I didn't know that before.

A PDF of the IBM AT Technical Reference would be very handy, but I have yet to find one...
 
Well, one could say, as virtually anything can be found at google, why should we post at this forum at all?

I'm sorry but questions -and answers- like the above for me is all what this forum is about, and I'm happy to read them.

Very often when I *do* a google search for vintage related things, I end up at...... this forum. I think it doesn't hurt if we contribute here and make sure things can still be found... through google or not.

I can see you do a lot of good work here mbbrutman, and its very much appreciated. But if you bolt the machine too tight, it won't run...

whoops, now this topic went completely off-topic, sorry about that.

EGA Card wise: I have an ATI EGA Wonder (could not find an original IBM one), but that seems to have different jumpers. Luckily I could still find those through google, I think there are more than on the original EGA's.
 
I'm happy that the switch settings are now posted here for posterity. But really, it seems like every time somebody gets a new machine we go through a wave of postings about things that we already talked about or are readily available on the net.

Not everything can be found in Google in a reasonable amount of time, and Google does not replace a discussion. But there is lots of reference material available already, so rather than rehash or repost what is available elsewhere, let's move up the food chain a bit and generate some new content/new discussion.

Discussions on how packet drivers work, how to modify machines in ways that were not intended, programming on old machines, etc. generally don't appear on Google because it is harder to come by. Those discussions are valuable and harder to find elsewhere.
 
Quite honestly, if I could easily find the information then I wouldn't have posted :roll:

As mentioned before, I check several sources before posting. The archives of Google Groups are fantasic, but then again, that's the problem, you can spent too much time in there :lol:

The IBM AT Guide to Operations doesn't have the switch settings in them either.
 
Googling...

Googling...

...Not everything can be found in Google in a reasonable amount of time, and Google does not replace a discussion. But there is lots of reference material available already, so rather than rehash or repost what is available elsewhere, let's move up the food chain a bit and generate some new content/new discussion.

Discussions on how packet drivers work, how to modify machines in ways that were not intended, programming on old machines, etc. generally don't appear on Google because it is harder to come by. Those discussions are valuable and harder to find elsewhere.

One of my favorite stories happened at least 10 years ago when I had a motherboard giving me a particular problem. All I had was the manufacturer's model number (later to be determined as from PC Chips). The fifth out of nine search results described my problem exactly, and gave a fix I ran within a matter of minutes to solve the problem.

Nowadays I think a search can bring back TMI ("Too Much Information"). If I did the same search today I'd probably have several thousand links to further weed through. At a minimum 75% of that information would have been how to run a flavor of Linux on the motherboard.
 
Yup, that one must have slipped by. I found several references to the switch settings for EGA, but no info about using it with a CGA display. Most of the info I found was for other brand EGA cards.

Another good thing about this forum is that there are a number of knowledgeable people who know exactly what you are after - instead of trawling through 15,000 pages of conflicting information on Google Groups which may or may not be correct :) I don't really want to take a trial based on someones unofficial troubleshooting posts from 1988 and potentially destroy my 5153 ;) As I posted before, I will always check other sources before posting.

Anyway, this thread now a lot longer than the 3 posts it should have been. Can we get back on topic?

The EGA card has a daughterboard that piggybacks onto it, which I assume is to add extra memory. Currently there is one row of chips fitted, and two rows are left empty.

From what I can find out, the card is fitted with 64kB as standard, the expansion increases on this. The chips fitted to mine are labelled as TMS4416-15NL, am I right by saying these are 16kB? To me, it seems a bit pointless in going to the extra expense of the daughterboard only to increase the video memory by 16kB. I was wondering if they would take 64kB chips, making the total 256kB (which seems to be the standard for most aftermarket cards).
 
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...The EGA card has a daughterboard that piggybacks onto it, which I assume is to add extra memory. Currently there is one row of chips fitted, and two rows are left empty.

From what I can find out, the card is fitted with 64kB as standard, the expansion increases on this. The chips fitted to mine are labelled as TMS4416-15NL, am I right by saying these are 16kB? To me, it seems a bit pointless in going to the extra expense of the daughterboard only to increase the video memory by 16kB. I was wondering if they would take 64kB chips, making the total 256kB (which seems to be the standard for most aftermarket cards).

Each chip is 4 bits wide (so two make a bank). Count the number of pairs and multiply by 16Kb. Remember these are the days of pretty minimal VRAM (since resolution and color depth was limited all you may get is more video "pages").
 
On followup, I can't seem to get the EGA card to work at all :(

I first plugged it in and get three bips "biiiiiiiiiiiiiiip bip bip", which I seem to recall means no graphics adapter is found. No matter what the switch settings, it is the same result. I also tried it without the daughterboard attached but no luck.

I guess this means my EGA card is dead? Also, would this be the reason my IBM EGA display went up in smoke?
 
'Seem to recall' - how firm is your memory? You'd really need the Hardware Maintenance book or a tech ref to decode the beeps. I thought it was two beeps for a video card RAM failure, but I would need to look it up. (I don't keep the good reference materials at work.)
 
I'd be willing to scan a few pages from my AT technical reference
and send them to you by email. I have PC-5150/XT-5160/PCjr/AT-5170 Technical References and also the Technical Reference Options and Adapters Vol 1-3 :) Took me awhile to complete the set !

I recall there is a large section in the Options and Adapters
on the EGA card. Probably 75 plus pages.

It gives the same beep codes when no graphics adapter is installed (and I have since found: http://www.bioscentral.com/beepcodes/ibmbeep.htm ).

I'd love to get an AT Technical Reference, however I've only been able to fint the XT one in PDF format. I'm just going to have to wait until one appears on eBay.

I guess there is no hope for the adapter then :(
 
If you have an EGAWonder, why bother with the IBM board at all? The ATI is far superior, IMNSHO. If no other reason, the memory max-es out at 256K vs. the IBM's 128K max (using 16x4-bit wide chips on-board & expansion daughterboard). The EGAWonder also has other 'special' features that are not available with the IBM EGA adaptor, such as the ability to display EGA resolution on a CGA monitor (via interlacing). I've used 'em in that mode, and, depending on the monitor, it ain't too blinding. I have one in my 5155 right now, and even considering the short persistance of the phosphor in the CRT, it still ain't very flickery (I've seen worse).

--T
 
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If you have an EGAWonder, why bother with the IBM board at all? The ATI is far superior, IMNSHO. If no other reason, the memory max-es out at 256K vs. the IBM's 128K max (using 16x4-bit wide chips on-board & expansion daughterboard).

I would dispute that. The basic IBM EGA board has 64KB, using 8 16k x 4 chips. The daughterboard has three rows supporting 8 16k x 4 chips each. If you fill all the rows with standard 16k x 4 chips, you can add 192KB to the 64KB on the motherboard to obtain the full 256KB that the EGA supports. The EGA uses 8-bit memory, so 2 16k x 4 chips = 16k x 8. Each row supports 4 pairs of 16k x 4 chips, and 16, 32, 48, 64. Now multiply that by four.
 
I can confirm that on a 5170, three beeps (1 long then 2 short) is video related.
That's what I hear when I remove the EGA card from my serviceable 5170.
 
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