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CMS80F731x Reference Manual
2.
Memory and Register Mapping
This series of Microcontrollers has the following types of memory:
◆
Up to 16 KB of FLASH program memory (shared by APROM and BOOT).
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Non-volatile data memory (Data FLASH) up to 1 KB.
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Up to 256B of general-purpose internal data memory (RAM).
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General External Data Memory (XRAM) up to 1 KB.
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Special function register SFR.
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External special function register XSFR.
2.1
Program Storage Flash
Program memory FLASH is used to store source program and table data, and the program counter PC is used as an
address pointer. The PC is a 16-bit program counter, so the address space that can be addressed is 64KB, but this chip only
has 16K bytes of program storage space.
The FLASH space allocation block diagram is shown in the following figure:
FLASH: 16KB
APROM
BOOT
3FFFH
0000H
After the chip is reset, the CPU starts executing from 0000H. Each interrupt is assigned a fixed address in the program
memory, and the interrupt causes the CPU to jump to that address to start executing the service program.
For example, external interrupt 1, which is assigned the address 0013H, if external interrupt 1 is used, its service program
must start at the 0013H location. If the interrupt is not used, its service address is used as a normal program store address.