All things ESDI

[James Fogg]

> I did some Googling on these drives last night and I found 
> plenty about geometry but little else. It seems ESDI fitted 
> somewhere between MFM/RLL and IDE all be it a very brief 
> appearance but certainly the rationale for introducing the 
> ESDI drives at the time was impressive for those times.

They came along just before SCSI and SCSI displaced them in the market.
They were excellent performers in their day.

> The connectors on the ESDI drive appear to be the same as MFM 
> so I am assuming that I can use MFM cables.

I always did, but cannot assure you it would be correct.

> My only 
> concern is that I could not ascertain if these types of 
> drives require the heads to be parked before spinning down so 
> I'm reluctant to do this at this stage.

They are "new" enough they should auto-park.

> clear. I am also assuming that if I slot an ESDI controller 
> into a motherboard that the motherboard will recognise it as 
> a hard disk controller without doing much else.

The PC type Adaptecs had a configurable BIOS overlay like the later SCSI
cards and would appear as a "standard" drive. Adaptec also made some
controllers that were intended for native support by OS's and hardware
designed for ESDI, such as the 3Com 3+Open servers (I used to support a
bunch of the 3Com servers).