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Help with Sergey's 8-Bit FDC and Serial Port board.

fjk61011 said:
Progress. I tried c8000 and I get the bios screen but no option to change the drive type
Click to expand...
But you should have seen the Multi-Floppy BIOS banner/splash text when you had the card at D8000. I went to my IBM 5150 (fitted with CGA + XT-FDC cards only), changed the XT-FDC's switches to start the ROM at D8000, and as expected, I saw the Multi-Floppy BIOS banner/splash text appear.

So the symptoms you experience are:
1. No problem with Sergey's card in your clone (at various valid ROM setting for the clone).
2. In the IBM 5150, at some (valid for IBM 5150) settings of ROM address, you see neither the Multi-Floppy BIOS banner/splash text, nor the following 'Press F2 ...' text.
3. In the IBM 5150, at some (valid for IBM 5150) settings of ROM address, you do see the Multi-Floppy BIOS banner/splash text, but not the following 'Press F2 ...' text.

As I see it, for now, the 'Press F2 ...' bit is irrelevant. The fact is that with only the CGA card and Sergey's card fitted in your IBM 5150, you should be seeing the Multi-Floppy BIOS banner/splash text for all valid ROM address settings. Something is wrong right there. Fix that first, then if the 'Press F2 ...' bit is still absent, work on that.

In the IBM 5150, are you sometimes changing ISA slots when you change the ROM address switches? Imagine a 'bad' ISA slot.

Now, with your setting of C8000, see if using the DEBUG technique at [here] shows the ROM at C8000.
If not there, the card must be putting the ROM somewhere else, but within the address range that the IBM PC BIOS searches for BIOS expansion ROM's.
If there, try setting the card back to D8000 and seeing if DEBUG shows the ROM at D8000.
 
"In the IBM 5150, are you sometimes changing ISA slots when you change the ROM address switches? Imagine a 'bad' ISA slot."

Yeah I had just thought of that myself.

Will try your suggestions tomorrow or Sunday. I'm off to bed now. Midnight here now
 
This all started in order to put mTCP on the 5150 via 1.44 Mb fdd. I have succeded in doing that. The cards in the 5150 are
1. CGA card.
2.EtherLink II card.
3. a half-length memory card.
4. XT-CF card with DOS 6.22
5. xt-fdc.
The 5150 boots to DOS 6.22,

There seems to be faulty ISA slots in the DTK XT-clone.. I have to test it properly
 
I thought you were testing Sergey's ISA FDC card in the 5150 with minimal config: Just the CGA and FDC fitted ?

Why do you think the DTK XT clone has faulty ISA slots ??, You said the FDC works in the DTK XT Clone ?
 
Malc said:
I thought you were testing Sergey's ISA FDC card in the 5150 with minimal config: Just the CGA and FDC fitted ?

Why do you think the DTK XT clone has faulty ISA slots ??, You said the FDC works in the DTK XT Clone ?
Click to expand...
Sergey's ISA FDC card works in some slots of the dtk xt
 
This is getting confusing, Can you stick to using one computer to test the FDC, Either your 5150 OR 5160 with just the CGA card and Sergey's FDC fitted and nothing else.
 
Testing with 5160 not DTK clone.

CGA card
360 kb FDD
Sergey's card.

Boots from A: drive DOS 6.22 but no BIOS Splash screen appears. The card must be set for Drive 0 360 kb.
 
fjk61011 said:
Testing with 5160 not DTK clone.

CGA card
360 kb FDD
Sergey's card.

Boots from A: drive DOS 6.22 but no BIOS Splash screen appears. The card must be set for Drive 0 360 kb.
Click to expand...
Okay lets stick to this setup for now.

As i said in post #71 Sergey's FDC will work without the BIOS installed, AS a low density FDC, Your 5160 is booting from the 360Kb floppy drive A: because the IBM 5160 BIOS supports 360k floppy drives.

Try the FDC in different ISA slots in the 5160, Have you got any IPA, Give the fingers on the FDC a good clean first if you can.

Go back to Modem7's post #81 and do the debug test's and let us know the results.
 
modem7 said:
Now, with your setting of C8000, see if using the DEBUG technique at [here] shows the ROM at C8000.
If not there, the card must be putting the ROM somewhere else, but within the address range that the IBM PC BIOS searches for BIOS expansion ROM's.
If there, try setting the card back to D8000 and seeing if DEBUG shows the ROM at D8000.
Click to expand...
What exactly am I looking for in the display?
 
fjk61011 said:
Could it be that I've set the dip switches but didnt update it with xtidecfg? I can't remember if i did.
Click to expand...
You don't do that with this card. You are thinking of the XT-IDE card, where the XUB BIOS needs to be reconfigured if the switches for the base I/O address are changed.

fjk61011 said:
What exactly am I looking for in the display?
Click to expand...
In the photo at [here], see how there are 8 rows of 16 bytes (displayed in hex), starting with 55 and ending at A5. That is what you expect to see.

In the screenshot that you have provided at post #94:
1. The error is because you did not put a zero after the colon. But as it turns out, DEBUG assumed zero.
2. Sergey's Multi-Floppy BIOS is there at C80000.
3. But the problem in that screenshot is that the first byte is reading as 58, not the expected 55. The first two bytes must be 55 and AA for the code to be recognised as a BIOS expansion ROM.

At the times when you see the the Multi-Floppy BIOS banner/splash text being displayed at boot time, that byte will be reading as 55 (and the other bytes reading fine as well).

If you repeat the DEBUG thing a few times, you may see different bytes change.

Considering that you are now reporting that the card sometimes does not work in the clone too, this is all pointing to the card.

I think your first repair attempt action is to reflash the BIOS on the card.
 
For some reason your pic is not downloading for me, Is it very large ??
 
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