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- Newsgroups: comp.periphs.scsi
- Path: sparky!uunet!bif!vic
- From: vic@cd.com (Vic Serbe)
- Subject: Re: Novice questions about SCSI terminology
- Message-ID: <BxvBJ7.A1J@cd.com>
- Keywords: SCSI-1, SCSI-2, FAST SCSI, single-ended, differential
- Organization: Central Data Corp., Champaign, IL
- References: <1992Nov13.221759.14191@ultra.com> <1992Nov14.190211.13256@ukw.uucp> <1992Nov17.042334.17278@robots.in-berlin.de>
- Date: Tue, 17 Nov 1992 16:09:06 GMT
- Lines: 44
-
- In article <1992Nov17.042334.17278@robots.in-berlin.de> karl@robots.in-berlin.de (Karl-P. Huestegge) writes:
- >lupe@ukw.uucp (Lupe Christoph) writes:
- >
- >So SCSI-2 is a subset of SCSI-1 at the command level.
-
- Actually, it's a superset. All SCSI-1 commands are included in the
- SCSI-2 spec, but not the other way around. A SCSI-2 CCS for a specific
- device might be a subset of SCSI-1, but not the whole SCSI-2 spec.
-
- >A lot of devices
- >are conform to SCSI-1 but only a few of them implement their interface
- >exactly as described in SCSI-2. There is no rule in SCSI-2 that was
- >forbidden in SCSI-1.
-
- There were a LOT of things that weren't forbidden OR recommended in
- SCSI-1. Simply, SCSI-1 didn't explicitly exclude many of the things you
- could do with it, but that weren't in the spec. It is a loose spec. I
- don't think anybody would disagree on that point. SCSI-2 is a better,
- more complete spec, but still provides plenty of lattitude for vendor
- unique stuff.
-
- >>SCSI-2 is a recent standard that not only incorporates CCS, but
- >>also some more device types, I believe. It also defines Fast
- >>(10 MB/sec) and wide (16 and 32 bit) modes.
- >
- >BTW, is there already such a generic wide-bus beast ?
-
- I'd like to know about it if there is. My current understanding on this
- (this is intended to be read as a question) is that that part of the
- spec is still in turmoil due to indecision connector types based on the
- intent to somehow remain SCSI-1 compatible (part of the SCSI-2 spec).
-
- >Karl-Peter.
- >
- >--
- >Karl-Peter Huestegge karl@robots.in-berlin.de
- >Berlin Friedenau ..unido!fub!geminix!robots!karl
-
- --
- Vic Serbe "Makers of the scsiTerminal Server."
- Central Data scsiSupport | PH# (800) 482-0315 x237 |
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