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Re: SCSI I & II

In article <bongini.151.2F43A902@law3.law.ucla.edu>,
STEPHEN BONGINI <bongini@law3.law.ucla.edu> wrote:
> 
> 	What's the difference between SCSI I & SCSI II. 

SCSI-2 is newer than SCSI-1.  :-)

The main difference is that many of the aspects of the interface are
better defined with SCSI-2.  More standard commands are defined for
each type of device, and the command parameters are better defined.
Many more devices and features are defined, such as audio support for
CD-ROM drives (SCSI-1 CD-ROM drives such as Apple's CDSC, CDSC+ and
CD-150 use proprietary audio command sets).

SCSI-2 also has options for increasing comms speed - Wide SCSI (16 bit
transfers, requiring a different cable) and Fast SCSI (maximum of 10
million transfers per second instead of 5 million, I think).  Wide
SCSI is not supported on the Apple II.  I don't think Fast SCSI is a
requirement - it will work with slower controllers (all SCSI data is
handshaked anyway).
-- 
David Empson
dempson@actrix.gen.nz
Snail mail: P.O. Box 27-103, Wellington, New Zealand