Date   : Fri, 20 May 1983 05:29:00 EDT
From   : Paul R. Grupp <GRUPP@mit-mc.arpa>
Subject: CPU-Z Memory mapping

The Godbout CPU-Z has a switch for setting the ON-BOARD memory to
"base page only" OR "global".  When S3 position 6 is OFF, the memory
on the CPU board will be used in PLACE of memory in ANY bank that
is selected.  The 4K of CPU memory can be RAM, ROM, or 2K of each.
Just be sure that not only in the code to switch banks in the "global"
memory but also the the stack pointer MUST be set to "global" RAM if
you do any CALLs, PUSHes, or anything else that tries to use the stack
while an extended bank is selected (out of BASE page).

This is a great feature of this board as many of todays higher density
memory boards don't allow for deselection of a "window" to make way
for "global" memory.  The only draw back is that any board OTHER than
the CPU-Z that address this memory window will get the MAIN memory
board and not the CPU-Z's memory.  This means that DMA is NOT possible
to this global spot of memory but will work in the rest of the address
space.
--Paul