Path: utzoo!utgpu!attcan!uunet!lll-winken!lll-lcc!ames!netsys!len
From: len@netsys.COM (Len Rose)
Newsgroups: comp.sys.att,u3b.tech
Subject: Re: Hanging a 2nd disk off a 3b2-310?
Summary: hardware or only software?
Keywords: Congruent Disks
Message-ID: <11442@netsys.COM>
Date: 30 Dec 88 03:39:46 GMT
References: <7057@batcomputer.tn.cornell.edu> <7259@chinet.chi.il.us> <982@vsi.COM>
Reply-To: len@netsys.COM (Len Rose)
Followup-To: u3b.tech
Distribution: comp
Organization: Netsys,Inc.
Lines: 20


I have to assume it's just a driver loaded that enables the controller
to access the extra cylinders.. I always thought that the controller
chip was the limitation..I am trying to get a data sheet on the controller
(NEC 7261) for another project .. 

I might guess that also like the original driver, Congruent may be stealing
an unused bit somewhere on the controller chip.. Until I see a data sheet,no
way to tell.

The project I mentioned was re-doing the driver so that one could have 4 drives *
running off the internal controller (4 drives each 8 heads/1024 cyls) without
having to resort to adding expansion disk controllers. The hardware is there
already,and I suspect the driver should be easy.

I believe there was some mention of this in an old issue of the 3B Journal,but
I don't remember which issue. 

 
* Example: Micropolis 1325 (8 hds/1024 cyl)