Path: utzoo!attcan!uunet!pilchuck!amc-gw!jwbirdsa
From: jwbirdsa@amc-gw.amc.com (James Birdsall)
Newsgroups: comp.sys.ibm.pc.hardware
Subject: RLL, sector remapping, and 1024 cylinders
Message-ID: <3343@amc-gw.amc.com>
Date: 1 Oct 90 20:41:12 GMT
Reply-To: jwbirdsa@polaris.amc.com (James Birdsall)
Organization: Applied Microsystems, Redmond, WA
Lines: 29


   I just ran into an interesting problem with an RLL drive.

   I have a Toshiba MK134 and a Western Digital RLL controller (8-bit, I
forgot to look at the model the last time I had the computer open). The
Toshiba is ~65M and has 7 heads. When the RLL 26 sectors/track are remapped
to 17 sectors/track, the number of cylinders is still under the BIOS limit
of 1024.
   I just tried to install a Mitsubishi MR535. It is the same size but only
has 5 heads, so the number of remapped cylinders is well over 1024, making
about 22M inaccessible.
   I tried Disk Manager (came with the drive) as a last ditch; it tried to
tell the controller BIOS to not remap the drive, but returned with the
message "THE CONTROLLER BIOS DOES NOT SUPPORT NONSTANDARD CONFIGURATIONS."

   So, even through I'm running the drive RLL, I'm only getting ~44M (which
is the MFM rating!). And Disk Manager (which I don't want to run but I want
the extra space more) can't help with my present controller.

   So, can somebody point me at an 8-bit RLL controller that CAN handle
nonstandard configurations?

   Thanks in advance.

-- 
---
James W. Birdsall        jwbirdsa@amc.com         71261.1731@compuserve.com
          Compu$erve: 71261,1731            GEnie: J.BIRDSALL2
For it is the doom of men that they forget. -- Merlin