Memory Configurations; Memory Map For Initial Program Loading State - Sharp MZ-80B Owner's Manual

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4.2 Memory configurations
4.2.1 Memory map for IPL state
When the IPL (Initial Program Loader) in the boot ROM starts, the file (cassette tape file or
diskette file) is read automatically. The memory at this time is as shown in the map in FIGURE 4.2.
Address
$0000~-------------c--~,
$07FF
t - - - - - - - - - - ,
$8000
empty
RAM(I)
32k bytes
Initial Program Loading
FIGURE 4.2 Memory map for IPL operation
Program File
Boot ROM addresses range from $0000 to $07FF. This IPL loads a system program (for example,
BASIC interpreter, PASCAL or Assembler) to the head of RAM
(I)
(the standard 32k-byte package).
In this state, the RAM (I) addresses range from $8000 to $FFFF. After loading, the addresses are
inverted from the IPL state to the normal state so that the system program is activated.
When the IPL RESET switch (one of two reset switches provided on the back of the MZ-80B) is
pressed, IPL is performed in the same manner as described above.