formatting MFM drives on a IBM PC

Tom Gardner t.gardner at
Sat Sep 30 18:12:44 CDT 2017

I think Chuck has it backwards, AT Attachment as defined by the ANSI
committee publically predates IDE.  Although IDE was used internally at WD
it did not surface publically until well after the ANSI committee adopted AT
Attachment, abbreviated ATA.  The AT in AT Attachment or ATA has never stood
for "Advanced Technology" although many presume so.

A (P)ATA drive never directly connected to an AT bus, nor for that matter
any other bus but always required some form of adapter, albeit very simple
in the case of the 5170 type bus.  

The AT Attachment compatibility is with the Task File register set which can
be sent over any interface parallel, serial, carrier pigeon, whatever.  A
SATA drive could be connected to a 5170 with an 5170 bus to SATA bridge or
more like a PATA to SATA bridge (with a  PATA HBA in the 5170) - PATA to
SATA bridges did exist and u might find one on eBay.  Booting would be a
problem and so would capacity but it should talk.

So Serial ATA makes sense to me


-----Original Message-----
From: Chuck Guzis [mailto:cclist at] 
Sent: Thursday, September 28, 2017 5:37 PM
To: cctalk at
Subject: Re: formatting MFM drives on a IBM PC

On 09/28/2017 05:12 PM, Jules Richardson via cctalk wrote:
> On 09/27/2017 09:59 AM, Ethan via cctalk wrote:
>> The idea of IDE, as my understanding, is the controller that existed 
>> as an ISA card was moved onto the actual drive, and then what became 
>> the controller was mostly just extending the ISA bus over to the 
>> drive.
> I actually have an IDE "controller" somewhere which is just a tiny PCB 
> with an ISA connector on one side and a 40 pin IDE connector on the 
> other, along with a couple of ICs (presumably buffers/latches, but I 
> don't know without finding it).  It's somewhat unusual, given that IDE 
> ports were normally included as part of multi-I/O boards, or (a little
> later) often incorporated into the motherboard.

IDE used to be called "ATA" - "AT Attachment"; i.e. something tailored to
the PC AT (5170) 16-bit ISA bus.

What I find perplexing is the acronym "SATA" for "Serial ATA".  The name
would imply that a drive can be connected to a 5170, but I'm not aware of
any SATA adapters for the 5170 PC/AT.


More information about the cctalk mailing list