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Did ever exist an 8-bit ISA card for ATA (IDE) hard drives?

Rauli

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This morning I have seen in the local flea market a guy selling a 286 board with 2 ISA cards. One was an 8-bit ISA card made by Seagate. It was very similar to a MFM adapter card I have, but I noticed it had 2 40-pin connectors instead. So, I'm sure it's not for MFM drives.

But, as XT-attachment (XTA) and AT-attachment (ATA) drives use the same physical connector... Could it be a rare ATA drive adapter for 8-bit ISA bus? (if it ever existed) or a more normal XTA drive adapter?

The card had a chip with a silver sticker with Seagate copyright, probably a ROM. After leaving the flea market I wondered if an XTA adapter or an ATA one would need or not a ROM, but I reached no conclusion.

If 8-bit ISA ATA drive adapters existed, the list must be very short. Does such list exist?
 
The ADP50 was an 8-bit ISA card to talk to 16-bit IDE drives, that's the only vintage board I've personally seen. Of course, the XT-IDE does exactly that nowadays, and is readily available, so while original cards are probably still pretty rare, they're no longer sought after at the levels they once were.
 
The card had a chip with a silver sticker with Seagate copyright, probably a ROM. After leaving the flea market I wondered if an XTA adapter or an ATA one would need or not a ROM, but I reached no conclusion.

Every HDD controller needs a ROM. This is because there is no 'standard' harddisk interface. Floppy controllers can be used without a ROM because IBM used a standard NEC765-compatible chip, and the code for this was in the standard PC BIOS. All clone BIOSes have also cloned these floppy routines, and all regular floppy controllers use the same NEC765-compatible hardware.
Harddisks were not part of the original PC, so there was no standard, and no BIOS routines included for HDDs.
Every HDD controller for a PC or XT would need its own BIOS routines to add BIOS-level access to the HDD, so that the main BIOS could boot from the HDD, and DOS could have sector-level access to the disk.
Even for XTA you need a ROM. But I think the MFM interface was most popular in those days.

ATs are a different story: With the AT, the ATA interface was standard, and it was included in the AT BIOS. So standard ATA controllers will not need a BIOS ROM in AT and clone machines.
 
There were computers that had XTA on the motherboard; in that case, the XTA support could have been included in the BIOS ROM.

Correct (in fact, the only two PCs I've ever had with an XTA interface have it on board), but in that case you wouldn't install an XTA card.
Basically both the extension XTA card and its ROM routines are 'rolled into' the mainboard+ROM in this case. This is not XTA-specific of course. Any other kind of onboard HDD controller would be implemented in the same way.

I would expect any XTA ISA-card to have a BIOS extension ROM chip on it, or at least require it to function (many early PC mainboards would have extra ROM sockets where you could install such). Either that, or you'd need to boot from a floppy and then load the BIOS routines as some kind of TSR before you can access the drive.
 
I know XT-IDEs, I have a couple of them. With "ever exist" I meant in the XT times, sorry for not being clear!

OK. So, being an 8-bit ISA card, it is normal to have a ROM, for XTA, and for ATA.

As I don't have any XTA drive, I'm not intereseted in an XTA card, so now the question is: Is there a way to know which type it is (XTA or ATA) before buying and trying?

No list of known 8-bit ATA adapters?
No list of known 8-bit Seagate adapters? (that should be enough, as it is a Seagate card).
 
The JUKO D16-X supports both XT and AT drives.

Very interesting, the 1st one, and dual XTA/ATA. Searching for pictures I found a thread about it here, in VCF: http://www.vcfed.org/forum/showthread.php?48957-Juko-D16-X-8bit-ISA-IDE-controller-is-it-any-good
They even dumped the ROM so it doesn't seem very hard to clone... except for the PAL chip (sigh!)


The 2nd one is very interesting, too. I found another thread in VCF about this card, but the photos are there: https://www.recycledgoods.com/acculogic-110-00415-00-side-1-16-isa-card/
No ROM dump, and those 2 chips covered with sticker are probably custom (PAL or similar) chips.
Maybe its for the photo quality, but this card looks like very recent in spite of being really old.

I think the card I saw this morning is XTA, it could be http://www.uncreativelabs.de/th99/c/S-T/20192.htm (it's Seagate, and the connector and jumpers layout is exactly like I remember).

But if somebody knows more ATA 8-bit cards, please, let me know in this thread.
 
I don't think Seagate ever made an 8bit ATA controller. The one you saw was almost certainly an XTA controller. One way to to tell the difference is if the card has two 40 pin headers on it. XTA did not support master/slave operation, so the XTA cards often had two headers to support two drives.
 
This morning I have seen in the local flea market a guy selling a 286 board with 2 ISA cards. One was an 8-bit ISA card made by Seagate. It was very similar to a MFM adapter card I have, but I noticed it had 2 40-pin connectors instead. So, I'm sure it's not for MFM drives.

But, as XT-attachment (XTA) and AT-attachment (ATA) drives use the same physical connector... Could it be a rare ATA drive adapter for 8-bit ISA bus? (if it ever existed) or a more normal XTA drive adapter?

The card had a chip with a silver sticker with Seagate copyright, probably a ROM. After leaving the flea market I wondered if an XTA adapter or an ATA one would need or not a ROM, but I reached no conclusion.

If 8-bit ISA ATA drive adapters existed, the list must be very short. Does such list exist?

Yes there was. I have one and it's in my 5160. It goes by 'VTI-XTB VER 2.0' and supports two IDE drives only- no floppies. There are no provisions for a mounting bracket on the card and it simply snaps into a 8-bit slot. One of its features is a 27C64A-20N BIOS which may be disabled by the J1 jumper.
 
I don't think Seagate ever made an 8bit ATA controller. The one you saw was almost certainly an XTA controller. One way to to tell the difference is if the card has two 40 pin headers on it. XTA did not support master/slave operation, so the XTA cards often had two headers to support two drives.

Yes, it has 2 40-pin connectors. It must be XTA, then.

Yes there was. I have one and it's in my 5160. It goes by 'VTI-XTB VER 2.0' and supports two IDE drives only- no floppies. There are no provisions for a mounting bracket on the card and it simply snaps into a 8-bit slot. One of its features is a 27C64A-20N BIOS which may be disabled by the J1 jumper.

Oh, I found a photo of that card here: http://www.minuszerodegrees.net/rom/photo/VTI-XTB version 2.0Y.jpg
It is the easiest card to clone, but... they say it's XTA, not ATA. Disabling the BIOS only makes sense in an 8-bit XTA card. An 8-bit ATA card should always have it enabled (unless you have a 2nd 8-bit ATA card). Which drive do you connect to this card?
 
. . . Which drive do you connect to this card?
The picture is correct, exactly what I have. I'll have to poke around to find the HD. I have the 5160 stored in the original packaging and container out in my garage loft. I pulled the HD and controller for some reason and just haven't got around to putting it all back together again. I don't remember the specs on the IDE, but it is one ancient looking critter. I'll get back to you on that when I track it down.
 
I believe I have an ADP50 in my original 5150 w/500MB IDE hard drive. And if I look hard I have a second 8bit IDE card floating around. I believe the ADP50 could only use a HD to 512MB anything bigger would not work. Their are also 8bit SCSI interfaces w/50 pin headers that you can use with SCSI HD in the 5150-5160's machines.

framer
 
I have an 8-bit card for ATA (i think), from Silicon Valley, and an XTA card from Western Digital IIRC.
 
Yes, it has 2 40-pin connectors. It must be XTA, then.



Oh, I found a photo of that card here: http://www.minuszerodegrees.net/rom/photo/VTI-XTB version 2.0Y.jpg
It is the easiest card to clone, but... they say it's XTA, not ATA. Disabling the BIOS only makes sense in an 8-bit XTA card. An 8-bit ATA card should always have it enabled (unless you have a 2nd 8-bit ATA card). Which drive do you connect to this card?

I found the drive and it's a Miniscribe 8450 XT manufactured 12/06/88. I believe it's about 40 MB or so.
 
The Seagate card to which the OP is referring is the ST-05X:

http://www.4drives.com/DRIVESPECS/DCTL/20192.txt

gt11412-seagate-80149-004-st-05x-bios-circuit-board.jpg
 
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