Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!newstop!sun!wonky.Eng.Sun.COM!mjacob
From: mjacob@wonky.Eng.Sun.COM (Matt Jacob)
Newsgroups: comp.periphs.scsi
Subject: Re: Slow clock speed gives faster data rate!?
Message-ID: <141509@sun.Eng.Sun.COM>
Date: 29 Aug 90 01:29:54 GMT
References: <33016@cup.portal.com>
Sender: news@sun.Eng.Sun.COM
Organization: Sun Microsystems, Mt. View, Ca.
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Yes- I've noticed this phenomenom too. Slower is not necessarily 'slower'.

Strictly speaking, the following might be true:

	+ A SYNC scsi host adapter chip (nameless) might make the statement
	in its manual 'Can receive SYNC data at 5.6mb/s independent of clock
	speed'.

	+ During SYNC negotiation, you tell the target you can go that
	fast. It tells you it can only go 4 mb/s.

	+ Due to integer rounding when you program the transmit maximum
	in the chip, this 4mb/s cooks down to 3.6mb/s.

	+ However, you may still be lucky and the target will still be
	able to transmit data to you at 5.6mb/s.


-matt