Need Help!- With TC-22 motherboard replacement

[jalessi]

If you look at the bios settings on a original motherboard that works you will see what the shadow or memory address for the card is.

Find an original motherboard!

Jeff...

[tpmx57]

I just found a used motherboard and it was not original and it worked just fine.
I bought 2 boards just to have an extra one if I ever need it.
My machine booted just fine first time.
I didn,t try the second board so I can,t say it is good but I will send it to you if you need another but I would bet the board is not the problem.
Follow Georges advice and you will get it going.
I do know someone in Canada that has an original and he wants $200 dollars for it.
I was going to buy it until he sent me closeups of the battery and it was leaking just like mine.
Board was still good and maybe you could swap out the battery and use it.
I paid $25 for the one in my TC now and it is fine.
It is 133mhz,the other I have is 100mhz.
Like I said I will send it to you if the problem ends up being the MB.

[cybermachineman]

OK, here is the latest. I swapped the BMDC cards, same problem, Machine 1 (original problem machine) still does not do the executive load. I put the BMDC from machine 1 in machine 2 (Working machine) and it loaded fine. I checked and the BMDC's were Identical part numbers. I believe it may be a BMDC address problem? The bios on each of the replacement motherboards is completely different and I did not get into computers until Plug & play was already around, so I will need a little help sorting out the problem.

[cybermachineman]

A bit of new news. When looking through my Maintenance Manual I found something that I missed earlier. It reads; The BMDC board is compatible with most IBM AT compatible systems. There are two requirements:
1. The I/O address 1A0 thru 1B6 (hex) are reserved for use by the BMDC board.
2. The memory addresses D4000 thru D4FFF (hex) are reserved for use by the BMDC board.

I went through every page in the bios and found no place to modify these setting? It sounds like I need a board with a more configurable Bios? EMI wants 1200.00 for a new motherboard and of course, it comes with DOM and new software, I can't just buy the motherboard! If someone has the exact model of motherboard that is working in their machine, please send me the number and I will try to find one like it.

[mactec54]

One other thing to check is the ribbon cable between the hard drive & the mother board

I have sent you a PM for a contact

I just read your post my friend will help you with your mother board etc he has the parts you need as well

[tpmx57]

I remember when I got my TC home It was stubborn to boot up after the trip.
I would keep getting back to the C:/ where I would type RUN and enter several times and finally it would start.
I ended up reseating all the boards and the problem went away for awhile then it started again,I thought the hard drive was acting up because I could wiggle the ribbon cable around on the drive and could finally get it to start.
I ended up replacing the ribbon cable to the harddrive and never had that problem again,forgot all about that till Mactech posted this.
Also here is a link to the motherboard I bought off Ebay and it worked fine:
http://cgi.ebay.com/ws/eBayISAPI.dll...=STRK:MEWNX:IT
Heres is the second board I bought to have a spare but never tryed it yet:
http://cgi.ebay.com/ws/eBayISAPI.dll...=STRK:MEWNX:IT
Stay at it you will get it.
Some good help on here.

[cybermachineman]

I got some good info today. There is something in DOS like a hardware integration layer. When dos is set up for the first time it makes a few little adjustments. The way it sounds sometimes you can switch motherboards with no problems, other times you have to re-setup dos so this integration layer file can look at the motherboard setup. It is kind of like putting a hard drive with a XP operating system straight from one computer into another computer. On boot up XP gets completely confused and crashes. Dos isn't nearly as complicated or fusy as XP, but my next move is to format Drive c:, reload DOS and then re-load the DX-32 software. I have 2 sources telling me this is the route to go. It will be a few days before I get the dx-32 software disks as I never got any with my machines, but as soon as I get them I will let you all know how it come out. Thanks for all the help to all that have replied.

[mactec54]

Hi just sent you another PM I think you had a email address problem

[cybermachineman]

PROBLEM SOLVED. We Formatted the Hard drive, reloaded DOS 6.2 and then reloaded the DX-32 software and parameters, The machine did the same thing, Would not do the executive load on the BMDC. We figured it Has to be Motherboard/BMDC conflict. We found on the Plug & play page of the Bios, a place that said: ISA shared Base Memory size, It was set to (Disable) we set it to 64KB. When we did this it then showed a previously hidden page that said: ISA shared memory address, we set it at D0000H. That was the fix. I don't think I needed to reload any of the sofrware, it was probably this memory address problem the whole Time, just as some of you suggested earlier. ( I just couldn't find where to adjust it)This was a good exercise and I learned a lot and now have DX-32 backup disks, all of which is a good thing. Thanks to all of you for all the help, Fred

[jalessi]

Cybermachineman,

I am sure someone else will have the same problem in the future.

Good to hear you solved the problem.

Jeff...