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csulaguy
May 16th, 2015, 08:26 AM
Hello y'all,

I recently acquired the ISA XT-IDE card (the small 8 bit card sans CF connector). Anyways, I am unable to read my floppy drives after it boots. I'm using a Modular Circuit Technologies FDC-HD4, which allows me to use a 1.44MB for the first drive and 360K for the second (has its own BIOS).

When I boot up using the XT-IDE card, it will find the first floppy, but cannot read any diskettes, and will not find the 360K drive at all. Is there something I'm doing wrong, or is this just a limitation of XT-IDE?

I was also told I should be able to use my Everex 391 MFM controller in conjunction with the card, but that doesn't work either.

modem7
May 19th, 2015, 02:49 AM
I recently acquired the ISA XT-IDE card (the small 8 bit card sans CF connector).

I was also told I should be able to use my Everex 391 MFM controller in conjunction with the card, but that doesn't work either.
What computer are you using the EV-391 in? Your other thread suggests that it is an IBM 5170 (IBM AT). From the manual (http://www.minuszerodegrees.net/manuals.htm#Everex)for the EV-391: "The EVERDISK subsystem comes mostly with the EV-391 controller board. The board is two-third sized, and is NOT AT-compatible."

The manual does not elaborate, but maybe the AT bus is too fast for the card.

If the computer is an IBM XT (or clone of), then yes, I would expect an XT-IDE card and MFM controller combination to work. In fact, the photo at [here (http://www.minuszerodegrees.net/images3/xtide_on_xt_clone.jpg)] shows such a combination in one of my XT clones. It is a different XT-IDE card [photo (http://www.minuszerodegrees.net/images2/xt-ide-gen-1.jpg)] and the BIOS is the 'XTIDE Universal BIOS', but the XT-IDE/MFM combination can be done. From memory, I had to put the MFM controller's BIOS ROM at a lower address than the ROM in the XT-IDE.


I recently acquired the ISA XT-IDE card (the small 8 bit card sans CF connector). Anyways, I am unable to read my floppy drives after it boots. I'm using a Modular Circuit Technologies FDC-HD4, which allows me to use a 1.44MB for the first drive and 360K for the second (has its own BIOS).

When I boot up using the XT-IDE card, it will find the first floppy, but cannot read any diskettes, and will not find the 360K drive at all. Is there something I'm doing wrong, or is this just a limitation of XT-IDE?
Does the FDC-HD4 work by itself without the XT-IDE card (and without the EV-391)? You do not say.

If not, and the computer is an IBM 5170, maybe the FDC-HD4's circuitry is clashing with the floppy circuitry on the MFM/floppy controller supplied by IBM in the 5170. I mentioned that in your other thread.