Oki ML63611, User Manual

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ML63611 User’s Manual
Chapter 2 CPU and Memory Spaces
2 – 7
OPTION B (D): 1.5 V (3.0 V), With regulator
circuit for LCD bias
OPTION A (C): 1.5 V (3.0 V), Without regulator
circuit for LCD bias
2.3 Memory Spaces
2.3.1 Program Memory Space
The program memory space is the read-only memory that stores program data.
The program memory space has a data length of 16 bits and extends from address 0000H to address 1FFFH.
In addition to program data, the program memory can also store ROM table data and the melody data. Figure 2-6
shows the configuration of the program memory space.
Program data
or
ROM table data
or
Melody data
40 words
8160 words
Interrupt area
0000H
0010H
0037H
1FFFH
32 words
1FE0H
Test data area
1FDFH
Figure 2-6 Program Memory Space Configuration
After system reset, instruction execution begins at address 0000H. The interrupt area from address 0010H to
address 0037H contains starting addresses of the interrupt processing routines that are executed when interrupts
are generated. (Refer to Chapter 4, “Interrupt”.)
ROM table data is transferred to data memory by ROM table reference instructions.
The melody data defines the tone, tone length, and end tone used in the melody circuit. After an MSA instruction
specifies the starting address, the melody data is automatically transferred to the melody circuit when a melody
data interrupt occurs. (Refer to Chapter 11, “Melody Driver”.)
Because the test data area contains program data for testing, it cannot be used as a program data area.