The switch sounds like an adapter I've seen up on eBay a
couple of times that supposedly allowed you to switch between the
standard screen ratio (90 x 60 dpi) and the modified Mac XL screen
ratio (72 x 72 dpi). Both times I've seen them listed, they included
the plate as you describe with the toggle switch though they didn't
include any additional information other than what the adapter did.
I'm sure those on this list that are more knowledgable about the Lisa
than I can provide additionl information on the part.
As for the ROMs, according to the SUN do-it-yourself guide
for the Lisa, the H/88 ROM set was used in the Macintosh XL with the
standard screen ratio.
Jeff
Just picked up a Lisa 2/10 and there's hope for
full recovery (it
tries to boot and spins the HD noisily, though there's some major
screen flicker happening). One mysterious thing though: on the back,
installed in one of the expansion slot covers, there's a little
silver toggle switch with no label. Some wires lead into the guts of
the Lisa and I haven't bothered to take it apart any further yet.
When I had it in one position and turned on the Lisa, it beeped
angrily three times and gave me an error code of 52 with the "I/O"
board icon x-ed out. That code is listed as a possible COPS chip
problem, whatever the heck that means. Anyway, it acts much happier
when that switch is in the other position -- no beeps or errors and
I get all the way to the "boot from" screen where it wants a floppy
disk.
Any idea about the Mystery Switch?
Also, just to verify that I'm not insane, H/88 ROMS are stock, right?
--
Collector of Classic Microcomputers and Video Game Systems:
Home of the TRS-80 Model 2000 FAQ File
http://www.geocities.com/siliconvalley/lakes/6757