The origin of the phrases ATA and IDE [WAS:RE: formatting MFM drives on a IBM PC]

Jules Richardson jules.richardson99 at gmail.com
Mon Oct 2 09:13:54 CDT 2017


On 10/02/2017 08:29 AM, allison via cctech wrote:
>
>
> On 10/2/17 8:22 AM, Jules Richardson via cctech wrote:
>> On 10/02/2017 01:46 AM, Alan Perry via cctech wrote:
>>> There was a call to form the CAM (Common Access Method) Committee of X3T9.2
>>> (SCSI-2) on 30 Sept 1988 and they first met on 19 Oct 1988. The primary
>>> goal was to come up with a SCSI subset to facilitate it support in multiple
>>> OSs and BIOS on PCs. At the first meeting, two items mentioned in the
>>> minutes seem relevant. 1. Jim McGrath of Quantum was interested in
>>> embedding SCSI in the drive without a physical SCSI bus and described
>>> problems with reference to the PC/AT.
>
> So in effect the IDE was a minimal interface that would interface to the
> computer bus
> with no more than buffering.

True, I suppose the command structure was more complex with SCSI. It's a 
shame though, it would have been nice if SCSI had been the PC standard, 
what with the large number of devices available, more flexibility, and 
performance potential.

> Early SCSI disks
> were MFM drives with Adaptec or Xybec host boards (SCSI to MFM, local cpu
> was Z80 on the adaptor).

Xebec... but yeah, and I forgot that they used a Z80 (I was thinking it was 
some Intel 80xx thing). I don't know if Xebec actually made a SCSI one, I 
think they may all have been SASI (at least the ones that I've used). I 
remember there was a little schematic in the back of the manual for a 
suitable controller.

Adaptec, Emulex and OMTI all made similar bridge boards... and there were 
probably others, too.

cheers

Jules



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