750 boot error

[Gene Spafford]

Greetings.

I've installed Jim McKie's modifed boot program on a number of 750
systems and it works great. (This is the boot program which loads the 
revision 98 microcode into Rev 7 cpu boards.)  That is, it works
great so long as the disk is being booted off of a Unibus disk.
I have tried installing the boot program on a 750 which only has
RM80 disks on a Massbus, and I get the following error when it
tries to open the pcs750.bin file:

Boot
:hp(0,0)vmunix
Updating 11/750 microcode: hp error: (cyl,trk,sec)=(42752,0,16) ds=150700<ATA,
ERR,MOL,DPR,DRY,VV>
er1=2000<IAE> er2=0 mr1=10 mr2=11777
super block read error
178376+64972+51772 start 0x102c

I really don't have the time or knowledge to go delving into the
boot program to figure out why the controller is being presented
with an illegal disk address (that's what the error bits indicate)
when it is trying to open the file.

Anybody out there got any suggestions and/or fixes?  Please *MAIL*
your responses to me.  I will summarize results to anyone indicating
interest in same.
-- 
Gene "3 months and counting" Spafford
The Clouds Project, School of ICS, Georgia Tech, Atlanta GA 30332
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