Mike Long wrote:
> 
> 
> 
> Most PC SCSI adapters (including all 154X cards) have BIOS ROM on
> them.  The card's BIOS ROM supplements the system's BIOS ROM so that
> the system can boot from a SCSI disk hosted by that card.  If the
> card's BIOS ROM is disabled or otherwise inaccessible, you can't boot
> from it.
> 
> One of two things is probably happening:
> 
> 1) The 1542CF's BIOS ROM is disabled.
> 2) The 1542CF's BIOS ROM is being mapped into the Pentium PC's address
> space at a location that is already being used by another chunk of
> ROM.  Hence the 1542CF's ROM is "invisible."
> 
> The solution to both problems is to use the 1542CF's software config
> tool to enable the card's BIOS ROM, and map it to an otherwise unused
> location in the ISA memory hole.

A few comments about what I bumped my head against:

	1) Check if your SCSI Card BIOS can probe the devices before boot.
	   That will tell you if the card is ok and talking to the SCSI
	   devices etc. If it can talk to the bus - well...

        2) I had an 'interesting' episode with and AST with onboard NCR
	   SCSI and an Adaptec 2742T card...

	What happened was I installed DOS and Netware on the disks while
	on the NCR controller and all worked fine, the box was unstable -
	it was later traced to incorrect memory - so I decided to put the
	Adaptec in. Well the Adaptec came up fine, but all I got was the
	'missing operating system' blurb - it ended up being that the
	NCR SCSI BIOS puts the partition table info/boot sector at a funny 
	offset that the Adaptec BIOS can't see 100%. 

	I don't know if this can apply between older and newer Adaptec
	BIOS revisions.

	I could get DOS to boot by booting of floppy and fdisk /mbr and 
	sys c: etc. But the Netware Volumes where missing... Swapping 
	the NCR back and after fdisk&sys  again all was well... phew! 
 

	50 Reasons why I hate PCs...

Just my 0.0111119

et
-- 
Ernst J. du Toit (TED5)           Internet: ernstjdt@maxwell.ctech.ac.za
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