From: sonny@charybdis.harris-atd.com (Bob Davis)
Subject: Installing More Than Two MFM Hard Drives on ISA PC Compatible???
Date: Sat, 5 Sep 1992 15:20:12 GMT
Reply-To: sonny@trantor.harris-atd.com (Bob Davis)
Organization: Advanced Technology Dept., Harris ESS, Melbourne, FL

	If I install two MFM Hard Disk controllers on the ISA Bus
and try to run 3 or 4 MFM Hard Drives, I can install (given that the
controller supports Primary and Secondary drive ports) one controller as
Primary and the other as Secondary. Seems some of my controllers which
support such arrangements thru jumpers on the board have a BIOS that can also
be selectively configured to maybe C800 or CC00 as the ROM start address. 
Other boards do not even HAVE an on-board BIOS to move around. 	
	Iam asking for help here, and I am guessing at a lot of this 
stuff (Heaven knows, all literature I have seen on this subject 
seems intent upon keeping all the secrets about multiple drive 
configuration to itself, even though it pretends to tell you how 
to do it!) I think the authors of this stuff really are trying to
tell you how to configure the drives, but *NOBODY* ever reads the
stuff from the viewpoint of a USER who has NEVER done this 
configuration before. This is nigh on to UNFORGIVEABLE and 
*really* makes the company which allows such documentation to 
escape look very, very bad. It never ceases to amaze me that the 
manufacturers of such great technology fall so utterly and 
universally flat upon their collective faces when it comes to 
communicating that technology to us unwashed masses...:-) 

	My questions:

	1. If the controller has a ROM BIOS extension, do I simply make sure
that one controller's BIOS is at, say, C800, and that the other controller's
BIOS is at, say, CC00 (i.e, at different locations)?
	Then, to low level format the first controller's drives, do I simply
enter DEBUG and do the g=C800:5 (details might change on this start location);
and then do I enter DEBUG and do the g=CC00:5 (or, whatever) to low level
format the drives connected to the second controller?

	2. For controllers which have jumpers allowing the Hard Drive
ports to be selected as either the Primaries or the Secondaries,but which
do not have any ROM BIOS extension on the card, do I then 
need some additional low level formatting software from the controller card
vendor to LL format the Primary and the Secondary controllers' drives?

	3. Given that I accomplish low level formatting of the 3 or 4 MFM
drives I have connected to the 2 controller cards, then does DOS find all
3 or 4 of the drives when I reboot? And then can I use DOS's FDISK and
FORMAT programs on all of them without needing to know yet still more
stuff??????

	Oh, I *do* hope you know some of the answers to these questions.
And if you are the writer of documentation that gets delivered to us poor,
disadvantaged souls, PLEASE RE-READ WHAT YOU WRITE FROM THE VIEWPOINT
OF A COMPLETE BEGINNER and do not be embarrassed to say the most obvious
of things... The smart folks can throw away words but the rest of us will
wish you had written more words and will praise your name to the Highest 
of the Heavens...

	Thanks.



_____________________________________________________________________________
Bob Davis, UofALA alum \\ INTERNET: sonny@trantor.harris-atd.com  |  _   _  |
Harris Corporation, ESS \\    UUCP: ...!uunet!x102a!trantor!sonny |_| |_| | |
Advanced Technology Dept.\\ AETHER: K4VNO          |==============|_/\/\/\|_|
PO Box 37, MS 16/1912     \\ VOICE: (407) 727-5886 | I SPEAK ONLY | |_| |_| |
Melbourne, FL 32902 USA    \\  FAX: (407) 729-3363 | FOR MYSELF.  |_________|

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