8 Jan
2009
8 Jan
'09
3:25 p.m.
Pete Turnbull (pete at dunnington.plus.com) wrote:
a 64KB (32KW) MSV11-D with a base address of 000000(8) responds to all
addresses from 000000(8) to 177777(8). It has a jumper to disable the
top page. Maybe you need to do that?
It's certainly possible that could be a problem, but I've been reading the
MSV11-D user's manual (it's on vt100.net) and it doesn't have a jumper to
disable the top page. Actually what it has is a jumper to _enable_ the
bottom 2K of the I/O page, so you can have a tiny bit of extra RAM in
systems without many I/O devices.
The MSV11 manual says only "factory configured modules will not respond to
bank 7 addresses..." and it then goes on to say how you can enable the lower
2K of bank 7 with the aforementioned jumper, but it's quiet about how it
decides what a bank 7 address is (i.e. does it monitor BBS7 or the address
bits?).
The only other jumpers on the MSV11-D are for battery backup and to select
the starting address.
Thanks for the suggestions, but I'm afraid I'm still puzzled...
Bob