ICD Ramblo XL, Инструкция по установке и эксплуатации

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Chapter 5-Using
RAMBO XL
TECHNICAL NOTES
Accessing the Extended Memory (for programmers)
RAMBO XL uses 5 "extra" bits of the PIA (at $D301) to enable the
extended memory and to select which bank of memory to access.
The 256K of memory is divided into 16 banks of 16K. Banks 0-3 are
your computers "main" memory banks which are normally used by
your computer. Banks 4-15 may be selected to appear at a window
from $4000-$7FFF when RAME is clear (logic 0). The function of
each bit of the PIA (port B) is as follows:
These bits select the RAM bank to appear at the 16K window
from $4000-$7FFF if RAME is enabled (clear). Programs that
are designed to use the extra memory of a 13OXE would use
banks $C-$F (12-15) since A2 and A3 are normally high and not
used as bank selects on the 13OXE. Note that only banks $4$F
(415) are valid. Banks 0-3 are main RAM banks and should not
be selected to appear at the window.
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