W79E825A Datasheet, PDF (12/127 Pages) Winbond – 8-BIT MICROCONTROLLER

W79E825A/824A/823B/822B Data Sheet
7 MEMORY ORGANIZATION
The W79E825 series separate the memory into two separate sections, the Program Memory and the
Data Memory. The Program Memory is used to store the instruction op-codes, while the Data Memory
is used to store data or for memory mapped devices.
7.1 Program Memory (on-chip Flash)
The Program Memory on the W79E825 series can be up to 16K/8K/4K/2K bytes long. All instructions
are fetched for execution from this memory area. The MOVC instruction can also access this memory
region.
7.2 Data Memory
The NVM Data Memory of Flash EPROM on the W79E825 series can be up to 256/128 bytes long.
The W79E825 series read the content of data memory by using “MOVC A, @A+DPTR”. To write data
is by NVMADDR, NVMDAT and NVMCON SFR’s registers.
FFFFH
Unused
Code Memory
FCFFH
FC00H
FBFFH
256 Bytes
NVM
Data Memory
Unused
Code Memory
Page 3
64 bytes
Page 2
64 bytes
Page 1
64 bytes
Page 0
64 bytes
FCFFH
FCC0H
FCBFH
FC80H
FC7FH
FC40H
FC3FH
FC00H
NVM Data Memory Area
4000H/2000H
3FFFH/1FFFH
16K/8K Bytes
On-Chip
Code Memory
0000H
CONFIG 2
CONFIG 1
On-Chip Code Memory Space
Figure 7-1: W79E825/824 Memory Map
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