VOGONS


First post, by dunarea

User metadata
Rank Newbie
Rank
Newbie

Recently installed a MFM NEC D3142 drive (40MB) on a Turbo-XT.
The board is common one with 640KB RAM and worked and still works fine with a XTIDE-CF.
The graphics is an OAK combo VGA/EGA. Currently setup for VGA output.
Everything went well, like LLF and installing some DOS. Actually runs MS-DOS 5.01.

It boots ok, can create directories, copy and delete files of any size anywhere, but...

It doesn't run almost any app which uses graphics be it VGA, EGA or ANSI graphics.
Coudn't run edit, Prince of Persia, checkit... Nothing.
The only one so far which worked is xtidecfg.
The system just freezes and nothing can be done. The caps lock and num lock still work after that. But all it shows is a blinking cursor.

Tried in another XT machine with the HDD+controller pair and it does the same. Just freezes. Tried with another MFM controller and the result was the same.
Changed the graphics card for an EGA and still the same.
With the same MFM+floppy combo controller, I can run anything from the floppy drive but not from the MFM HDD. From the HDD only text mode apps.

Never had in the past such an issue.

Reply 1 of 5, by Jo22

User metadata
Rank l33t
Rank
l33t
dunarea wrote on 2020-06-25, 09:43:

With the same MFM+floppy combo controller, I can run anything from the floppy drive but not from the MFM HDD. From the HDD only text mode apps.

Never had in the past such an issue.

Hi, can you run CheckIt! off the floppy disk ? If so, check the memory browser.
It's just a wild guess, but maybe the controller's ROM is conflicting with the memory location of the framebuffer.
Textmode appears on two positions, depending of the graphics card (CGA/MDA etc).
Perhaps that's why it works.

Anyway, it's just an idea. Maybe fellow vogons users can help figuring out the issue..

Good luck! 😀

"Time, it seems, doesn't flow. For some it's fast, for some it's slow.
In what to one race is no time at all, another race can rise and fall..." - The Minstrel

//My video channel//

Reply 2 of 5, by dunarea

User metadata
Rank Newbie
Rank
Newbie

I checked .
I'll abstaint to evaluate and leave it to more experienced guys.

Attachments

  • 2020-06-26_09h31_18.png
    Filename
    2020-06-26_09h31_18.png
    File size
    1.25 MiB
    Views
    116 views
    File comment
    checkit 3 I/O output
    File license
    Fair use/fair dealing exception

Reply 3 of 5, by pentiumspeed

User metadata
Rank Oldbie
Rank
Oldbie

Make sure the MFM controller card is set to standard settings that XT requires. The controller also has to be 8 bit as well.

Interrupt, rom address, and DMA address etc. Also use the low level formatter to pick interleave ratio so XT & DOS can process the sectors without falling behind. If 4.77MHz XT around 6:1, XT 8MHz, use 4:1 etc.

Yes, XT is very slow. Even 286 needed around 3:1 to 2:1 to work.

Cheers,

Great Northern aka Canada.

Reply 5 of 5, by dunarea

User metadata
Rank Newbie
Rank
Newbie

The controller is an HC-100 Transteque with dynamic configuration. Jumperless.
I set the interleave to 6 on my V20 XT machine. Tried before 3, 4 to 1 interleave and symptoms were the same.
The xtidecfg executable runs well with his ANSI interface, and is big enough to span many cylinders. Other software, no. Not even edit.com.

What is strange is if I pull out the MFM controller and use only the XTIDE-CF card, everything is fine. It is like that BIOS has something better inside...