23 Mar
2000
23 Mar
'00
4:16 p.m.
I think he's talking about the opposite of what you
mean. You mean using
RAM as a disk, right? I believe he means using disk for RAM. Which is
something I personally try to avoid like the plague!
Actually, it gets more confusing with RT-11, since the term 'virtual
memory' refers to the address space a program can access... it has
nothing to do with disk space...
The way to think of it is -- physical memory is the memory the machine
has while virtual memory is what a program can see at any one time.
And with 16 bits worth of address space, that maximum is 32kw (64kb)
at any one time... of course, you can remap portions of your address
space to elsewhere in physical memory, but you are always limited to
accessing 64kb at one time (128kb -- 64kb I-space and 64kb D-space if
you have a processor with separated I and D spaces)
Megan Gentry
Former RT-11 Developer
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