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From: tomb@tekecs.UUCP
Newsgroups: net.arch
Subject: More on disk interfaces
Message-ID: <5153@tekecs.UUCP>
Date: Thu, 28-Feb-85 12:31:19 EST
Article-I.D.: tekecs.5153
Posted: Thu Feb 28 12:31:19 1985
Date-Received: Mon, 4-Mar-85 06:12:40 EST
Sender: tomb@tekecs.UUCP
Organization: Tektronix, Wilsonville OR
Lines: 24

SMD is widely referred to as a 10Mb/sec interface and that's
a pretty good nominal figure but the "specified" data rate
is 9.677 Mbits/sec +/- the rotational accuracy of the drive.

ESDI as currently implemented (if you can really find anyone
with a product :-) ) is also a 10Mbit/sec  I/F. I hyave heard
claims that ESDI can be stretched to 20 Mbits/sec but that's
still future.

In the meantime, the whole concept of 
	System interfaces: Computer to controller
	Device interfaces: Controller to disk
is becoming less meaningful as people are migrating
VLSI implementations of system level interfaces directly
into their drives and the old device interfaces no longer
exist.

Tom Beach

email: ..!tektronix!tekecs!tomb
-- 
Tom Beach

email: ..tektronix!tekecs!tomb