Subject: Re: Fix for AHA-1542CP
To: David Rosenthal <>
From: Rodney W. Grimes <>
List: netbsd-bugs
Date: 09/18/1995 17:18:21
> The current Adaptec ISA SCSI Host Adaptor is the AHA-1542CP.  It returns
> boardid 0x46.  The NetBSD 1.0 and current drivers assume that any board
> with an unrecongized boardid does *not* need its mailbox unlocked,  so
> they don't work with the 1542CP.  Note that the 1542CP probably
> needs to be configured with the Plug-and-Play BIOS disabled in all systems,
> certainly in mine.
> You need to assume that future 1542s and clones will need their mailbox
> unlocked,  so that NetBSD doesn't fail every time they rev the BIOS.

I have from a rather authoritive source that all board ID's greater than
or equal to 0x43 will infact need to have the mailbox interface enabled.

The authority is Roy Neese of adaptec engineering who helped me to get
the information needed to add this hunk of code to the aha1542.c driver
way back when the 1542C came out.  The check should simply be changed
	if ((inquire.boardid >= 0x43) ||
	    (inquire.boardid == 0x41 && inquire.revision_1 == 0x31 &&
					inquire.revision_2 == 0x34)) {

Note that the 0x41 id is a reved 1542B with the 3.20 roms and a >1G drive
attacked.  This is a special case :-(.

Rod Grimes                            
Accurate Automation Company                 Reliable computers for FreeBSD