SCSI and 386/ix

[Steve Nuchia]

In article <PCG.90Feb5190711 at rupert.cs.aber.ac.uk> pcg at rupert.cs.aber.ac.uk (Piercarlo Grandi) writes:
>This perplexes me. You sure that a WD1003 style controller can
>overlap seeks? Are there any that do? I can hardly imagine seeks
>not being synchronous to the controller with a WD1003 style
>controller, that must issue step pulses to the head.

Most high performance drives being sold today buffer the step pulses and 
optimize the head trajectory, so the controller could in theory diddle
with the other drive while waiting for the ready indication.

>Are there really any RLL or MFM controllers (the WD1006 is by
>your implication) that can step independently the two arms?

I've never seen any information on how to make any of them do it.
-- 
Steve Nuchia	      South Coast Computing Services      (713) 964-2462
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