Sharp MZ-700 Owner's Manual page 129

• When the reset switch is pressed together with the
I
CTRL
I
key, addresses $0000 to $0FFF and
from $DOOO to $FFFF are assigned to RAM.
• When the # command is entered after the reset switch has been pressed, the computer operates in
the same manner as after the reset switch has been pressed together with the
I
CTRL
I
key.
4.2.5 Bank switching
a) Memory blocks can be selected by outputting data to I/0 ports as shown below.
SWITCHING
1/0 PORT
$0000"'$0FFF $D000"'$FFFF
$EO SYSTEM AREA (D-RAM)
------
$El
--------
SYSTEM AREA (D-RAM)
$E2 MONITOR (ROM)
----
$ E3
-----
V-RAM, KEY, TIMER
$ E4 MONITOR (ROM) V-RAM, KEY, TIMER
$ E5
----
Inhibit
~
Return to the front of
$E6
condition, where being
inhibitted by $ ES .
Note : Outputting data to I/0 port $E4 performs the same function as pressing the reset switch.
b) Examples :
OUT ($EO), A
Assigns addresses $0000 to $0FFF to RAM, but does not change execution address. The contents
of variable A do not affect the result.
OUT ($E4), A
Initializes memory to the state immediately after the power has been turned on.
Note : Since the program counter is not moved by the OUT statement, care must be taken when switch-
ing memory blocks if the program counter is located in the area from $0000 to $0FFF or from
$DOOO to $FFFF.
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