gregl@tekgen.UUCP (05/24/86)
If you want to read about the SCSI (Small Computer Systems Interface),
you can find a great article by Steve Ciarcia in the latest (May '86)
BYTE magazine. It's a two-parter (part two next month), and although
he specifically talks about the NCR 5380 SCSI chip and hooking it onto
his SB180 board, he clues you in on:
o the background of SCSI (SASI and the ANSI subcommittee)
o its various system architecture implementation schemes
o the physical hardware interface
o the logical interface
Next month, he plans on detailing the communications of the protocol
and the different bus phases. I recommend this series for those who
have little knowledge of SCSI (like me! :-) . It's very well written
(like all his articles -- can you tell I'm a fan?).
I've also read up here on the net people saying that SCSI is just SASI
with a name change. According to Ciarcia, this is true of SCSI _in_its_
_simplest_form_. To quote:
"SCSI in its simplest form is just a SASI interface. SASI designs
assume that one host will select a peripheral device, most likely a
disk drive, and remain connected to it until the I/O transfer is
completed. Because these products are used in low-cost, low-performance
applications, single-ended configurations that do not support parity
are the most popular."
-- Steve Ciarcia
"Adding SCSI to the SB180 Computer
Part 1: Introduction"
BYTE Magazine, May 1986
Apparently there are more sophisticated SCSI implementations out there
which are NOT the same as SASI (e.g. multi-processor and/or multi-tasking
architectures). Anybody care to comment?
-----------------------------------------------------------------------
Greg (can you say LAYOFF? There, I knew you could. :-) Lacefield
...!tektronix!tekgen!gregl
^^^^^^^^^ (for now!)
Disclaimer: The above endorsements are my own, not of my employer,
whomever THAT might be :-) <---- pasted smile