Subject: Re: asc vs esp
To: Jonathan Stone <>
From: Jason Thorpe <>
List: tech-kern
Date: 01/21/1997 16:05:38
On Tue, 21 Jan 1997 14:53:18 -0800 
 Jonathan Stone <jonathan@DSG.Stanford.EDU> wrote:

 > The chip in Decstations, Turbochannel Alphas, and (AFAIK) Macintosh
 > systems, is an NCR 53c94, or some variant  thereof.
 > How is this an `Emulex SCSI processor'?
 > Is there some shared ancestry between Emulex and NCR for this chip?

I guess Sun just used the Emulex chip, which is software-compatible
with the NCR 53c94.  Actually, I'd heard the name was "Enhanced
SCSI Processor", similar to the "Advances SCSI Controller" name
used by NCR... Whatever :-)

 > This, btw, is part of the reason I don't like the 2940 et. al. driver
 > being _the_ "ncr" driver.  Why should that particular family of ncr
 > products be `ncr', rather than, say, 53c9[34] drivers, or the ncr5380
 > driver(s)?

Just to nit-pick, the 2940 is an "ahc" ... (aha = Adaptec Host Adaptor,
ahb = aha++, ahc = ahb++, I guess :-)

I agree, however, that calling the NCR 53c810 driver "ncr" is
inappropriate.  It should be called "siop", since it's the
NCR SCSI I/O Processor.

Jason R. Thorpe                             
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