here's a dumb question

Erin W. Corliss erin at
Fri Jan 22 04:26:54 AEST 1999

OK, so I was at my ISP the other day and after a talk with the owner I
walked home with a bunch of pieces from a microvax II, which I used to
completely pimp out my PDP-11/73...  One of the new pieces is a hard
drive, which allows me to write assembly code with the RSTS/E Macro
Assembler, write them to the hard drive, and boot the system up in
non-RSTSish ways...

I'm new to PDP-11 assembly language, however, and I don't have a really
complete manual...  The general purpose registers are all 16 bits.
Addresses stored in these registers can only point to the first 32K words
of memory.  My PDP has a 512K words of memory.  The only reference I've
seen to this problem was one sentence in one of my manuals that says the
rest of the memory can be addressed through "memory management".  When it
says this, does it mean that there is a separate memory management unit
that I have to control to flip between pages or banks of memory, or are
there extended registers in the CPU itself that allow me to do this?  I
crashed the machine the other day and I noticed that the monitor listed
some registers that started with M...  Could that be what these are for?
(The computer claims to have 22-bit addressing, BTW.)

	-- Erin Corliss

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