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16-bit controller card in an 8-bit ISA slot

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Compgeke

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I've recently aquired 2 AT&T PC6300's and both have only dual floppies. The only hard drive controller card I have is a 16-bit BIOS-less one that has an IDE, a Floppy, a Game Port and a Parallel port. The only port I would be using is the IDE which raises the question, would I need the 16-bit support for the IDE and more specifically, would I even be able to use this card since it lacks it's own BIOS?

The model of this card is Koutech KW-557A.

Thanks!
 
Then unfortunately you need an 8-bit IDE controller. They do exist but are rare and almost certainly won't work with anything other than an 8-bit IDE drive, hence why some good folk on this forum developed the XT/IDE board for exactly this purpose (complete with boot ROM).

However I don't know of any of 'the original' board currently available. Several new versions are currently in test though.

Best bet is probably a post in the wanted section at the moment.
 
Well, to be fair, the 6300 does have 16-bit slots; its just that the "upper" slot is a proprietary design (38 position). You don't get cascaded PITs or DMA, but you do get the upper bus (the CPU is an 8086). Fortunately, the upper bus connector is at the far end of the card slot, so it might be possible to devise an adapter with a small paddle card and some ribbon cable to at least map some of the signals to fake a 16-bit ISA slot for some cards that occupy only a half- or three-quarter-length ISA slot.
 
Mapping the extra 8 data pins over to the proprietary slot in a 6300 is an... interesting idea, but it wouldn't really help much in this case even if would enable an AT IDE card to technically "work" because the of the 6300's lack of an AT drive BIOS. (I do wonder if there are other differences between the 8086/88 and 80286 buses that a standard IDE card would trip over, but I couldn't even make an educated guess without consulting the old PC Hardware Bible.) Without a BIOS... I guess back in the mists of time I used BIOS overlay software to add support for a tertiary IDE drive to an old 486 that only supported a single pair of drives (the hardware was a second multi-IO card that had a jumper for moving the IDE port to the secondary I/O addresses), and there were DOS drivers for CD-ROM drives on secondary IDE ports so... I suppose in *theory* if you could get the hardware working you might be able to cobble together some sort of boot disk which would let you enable a drive on it. Maybe.

Bizarre thoughts like that aside your best bet might be to find an 8-bit compatible bootable SCSI adapter, which is probably somewhat more common than an XT-compatible IDE card that works with modern drives.
 
I was thinking about finding a SCSI card since I've got many types of SCSI drives (from 3.5" drives to full size dual height 5 1/4" drives). The next step is finding a SCSI controller though since the only ones I own are PCI ones (and one PCI-x one in my server).
 
Well, I got the wild idea of testing the cards anyways (found another one in a sealed bag I didn't know I owned) and well, nothing, as I expected.

There is one odd thing about the older one (there is one with an older and one with a newer rom revision), when booting right before it checks for the floppy disk it says "Fixed Disk: Not Installed" while the newer one doesn't display that. Does that mean that the BIOS in that one will support a controller without a BIOS?

Edit: never mind, I looked in the repair manual and it has support for a Western Digital controller, wonder how hard that would be to find? Meh, I would rather find a SCSI controller anyways since SCSI disks are easier to find.
 
Well the T130B hangs on BIOS initialization. I wonder if this is related to the Tandy 1000TL/2 issue. At any rate, I'll load the BIOS up on a debugger and see what's going on. Probably something stupid simple.
 
As a fellow 6300 owner, I'm extremely curious to know what you find. Not because I plan on running a T130 in my 6300 any time soon, but because I am very familiar with them and am curious what the stumbling block turns out to be.
 
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