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XT-IDE rev2 "Optional ROM bad Checksum"

wesleyfurr

Veteran Member
Joined
Jul 16, 2009
Messages
612
Location
Virginia, USA
I helped someone out by putting together an XT-IDE rev2 board. I set it up and loaded basic boot files onto a DOM flash drive using a 486 machine, then tested it out with scandisk, Norton, etc. on both the 486 and my IBM 5155. Everything worked great. Shipped it to them, and when they put it in an XT clone, they are getting this at boot:

Phoenix 8088 ROM BIOS Version 2.51
(copyright, etc)

C8000h Optional ROM bad Checksum = 81h
Disk Bad.
Error. Press F1 to continue

Has anyone run into something like this before? I'm waiting on confirmation as to whether the power lead to the DOM is properly connected, but I don't know where to go outside of that and possibly testing it in another machine...

Many thanks in advance,

Wesley
 
C8000h Optional ROM bad Checksum = 81h
This means that the option ROM BIOS at segment C800h failed the checksum test. Since the board worked in your machines, I'd say there's another option ROM at the same location that conflicts with the XT-IDE v2 board.

What kind of clone is this? I'm guessing it aleady has a (possibly integrated) harddrive controller. That needs to be disabled unless you can move the XT-IDE ROM to another segment address.

Disk Bad.
This is odd but I guess it must be coming from the system BIOS.
 
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This means that the option ROM BIOS at segment C800h failed the checksum test. Since the board worked in your machines, I'd say there's another option ROM at the same location that conflicts with the XT-IDE v2 board.
A VGA card is a possibility. Refer to the 'Possible ROM conflict - hard disk controller and VGA' section at [here].
 
I'm pretty sure the original MFM card has been removed...but I've asked to be sure. What you say makes sense, especially if the XT-IDE BIOS doesn't have anything that would say "disk bad". Hopefully it is that simple.

I configured the XT-IDE card to the same settings as the original MFM card (according the jumper settings I saw in a photo of it and referencing online jumper setting listings for that particular controller). Unless the XT-IDE controller takes up a larger address range than the original MFM controller, I wouldn't think that would be a problem.

I'll also check and see, but the screen shots (as in camera photo) are of an amber display, presumably monocrhome...

Thanks,

Wesley
 
Long story, but still waiting to find out. Based on further conversation, there is a real possibility the old MFM card is installed as well...but waiting to hear back for sure. May be another week or so before I know more... Will do my absolute best to try to remember to post the results back here!

Thanks,

Wesley
 
Quick update...you were dead on Krille. The old hard drive controller was still in the system, and causing the problem. But...just to keep us on our toes, there were actually two different problems. The "disk bad" error was because there was a problem with the floppy drive. Somewhere along the way the data cable had gotten flipped. Then it's a fancy I/O and floppy controller that also has an NiMh barrel battery that was leaking...presumably that has caused a failure in the card. They swapped it out for another I/O/FDC card and the disk bad error went away.

Thank you very much for your help!

Wesley
 
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