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

Christian Corti cc at
Thu Oct 5 04:53:54 CDT 2017

On Wed, 4 Oct 2017, Guy Sotomayor Jr wrote:
> Also, the early desktop PS/2 (model 50 and such) had the controller 
> integrated on the drive and those were Maxtor as I recall.  The PS/2 
> shipped in 1987 and we had the drives in labs at least 12-18 months 
> prior (memory is dim on this right now).

No. The IBM 8550 has the controller on a special card and the drive had a 
PCB edge that inserted into the PCB connector on the side of the 
controller. The 8550-021 used a 20MB IBM WD-325N disk drive (P/N 90X6806). 
The controller is a ST-506 type MFM controller (with DMA, so it rocks with 
a sustained data rate of above 500kB/s!). My father upgraded the system 
with a standard Rhodime 50MB MFM drive. There was a purely passive adapter 
that split the card edge connector into the normal 20+34 pin connectors 
plus power. I still have that system and drive :-)


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