17 Dec
2003
17 Dec
'03
5:51 p.m.
Yes, well, it's also possible to use Unibus memory
on an 11/70, but
you have to set jumpers on one of the CPU cards. The Unibus memory will
not be cached, nor will the RH70 Massbus adapters be able to access
it.
You are limited to 124K words of memory on the Unibus. On the 11/45
that's all the memory the machine can address, and yes, you can have it
all on the Unibus. On the 11/70, that's only a small fraction of the
address space. It seems perverse to have a CPU capable of 22 bit
addressing, and with fast Massbus interfaces, and then cripple it like this!
I suspect you can use Unibus memory on the 11/44 too, with similar
restrictions.
-tony