[comp.sys.amiga] A1000/Comspec/Progressive Peripherals, expansion bus problem

kherron@ms.uky.edu (Kenneth Herron) (12/20/89)

Hello,

Some time ago I purchased a 2-megabyte memory board (Progressive 
Peripherals Megaboard 2, "When Quality Counts").  I had to perform the
PAL-ground mod (as well as connect a capacitor on the daughterboard with
one on the motherboard) to make this board work, but it's been utterly
reliable since then.

I just bought a Comspec SA1000 scsi controller (I don't have a disk yet,
but after hearing about Comspec not stocking A1000 items anymore, I
figured I'd better order while the orderin's good).  I hooked everything
up together (the memory board has no pass-thru so they can only be attached
one way) and tried to boot the Amiga.  It reads Kickstart fine; the 
Comspec tries to boot from the non-existant harddrive, and fails, just
fine; it asks for, and recognizes, a workbench diskette just fine.  But
while booting from the workbench disk, the system hangs in the exact
same way it used to hang with the memory board, before I grounded the
PALs (Ie, it stops dead either on the white screen or just as the initial
CLI is started).

The system boots properly with just the memory board, or just the Comspec
unit, installed (of course with the Comspec installed it tries to boot
from the hard disk first).

Now, given what I've heard about Comspec, and the history of this
memory board, I DON'T think the Comspec is faulty here, unless it has a
defective bus pass-thru.  I DO think this *MAY* be normal behavior for
a Comspec unit with something on the pass-thru and no hard disk, or,
more likely, that the PAL ground mod is not sufficient to handle these
two devices on the bus.

Does anyone know of a way to make the PAL ground "better", or other
ways to improve the situation?  Any sage advice out there?

Are Comspec or Progressive Peripherals on the net?  I'd love to talk
to either or both companies about this problem...

Thanks in advance for any help you can give,

Kenneth Herron