3b2 disk limit

[Greg A. Woods]

In article <1990May2.142538.4822 at nebulus.UUCP> dennis at nebulus.UUCP (Dennis S. Breckenridge) writes:
> paul at voicebox.dialogic.com (The Imaginative Moron aka Joey Pheromone) writes:
> >However, I have heard that some early /300's (with flat pack processor
> >chips,which mine has) had problems addressing large disks, because of
> >a disk controller bug. My informant was vague about the numbers, but
> >he said 30mb would work, but > 50 mb wouldn't.
> 
> Once you have the mod in, then the 3B2/300 will support 2 * 72 megs. 
> I have not tried anything like (boo hiss yuck :-) *Maxtor* drives but
> I am sure that woods at robohack could expand on what is required there.

Yup, Maxtor's work fine!  Well at least one of mine does...
(If anyone has any Maxtor carcasses, I'm interested.)

> The standard drive is the CDC WREN-II, but you can drop in pretty 
> much any drive that meets the CDC spec (Hitachi, Micropolis, Fujistsu)
> You also mentioned devtools. The new and improved version of this
> is called idtools. You may want to track a copy of it down.

Yes, idtools lets you do almost anything with a disk, as long as you
know the drive geometry.  The only restrictions seem to be 15 head,
1024 cylinders.  You can even change the number of sectors per track,
though 18 is the optimal number for standard ST-506 systems.  I've not
tried 1024 byte sectors, though it even appears you can change the
sector size too.

Idtools does the low level format, verify, bad-block table entry and
editing, disk copying, sanity track writing, etc.

I currently have 2 Maxtor-1140's installed, as 15h x 1024c x 18s x 512b.
(Most 1140's will format out to 1024 cylinders, though they are only
supposed to go to 918.  Some only go to 900.)
-- 
						Greg A. Woods

woods@{robohack,gate,eci386,tmsoft,ontmoh}.UUCP
+1 416 443-1734 [h]   +1 416 595-5425 [w]   VE3-TCP   Toronto, Ontario; CANADA