43
4.2.2 Memory map for normal state
When the machine shifts from
the
IPL state
to
the
normal state, the memory becomes
as
shown in
the map in FIGURE 4.3.
Address.--------------,
$0000
RAM
(I)
32k bytes
$7FFF~
--------------------~
$8000
RAM
(II)
32k bytes
(expansion area)
$FFFF~--
------------------~
FIGURE 4.3 Memory map for the normal state
In
the
case
of
the
32k
bytes standard
RAM
, addresses range from $0000 to $
7FFF;
in
the
case
of
the
64k
bytes full RAM,
the
address space consists
of
the
full area from $0000
to
$FFFF.
When addresses are changed from
the
IPL state
to
the
normal state
or
vice versa, the operation
is
controlled
by
output
terminal signals
cl'
c3
of
port
c
of
the
8255
as
described later.
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