W78E516DDG Datasheet, PDF (14/90 Pages) Nuvotem Talema – 8-BIT MICROCONTROLLER

W78E516D/W78E058D Data Sheet
8 MEMORY ORGANIZATION
The W78E516D/W78E058D 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.
FFH
Indirect
Addressing
RAM
80H
7FH
Direct &
Indirect
Addressing
RAM
00H
SFRs Direct
Addressing
Only
FFFFH
FFFFH
64K Bytes
External
Data
memory
64k
Bytes
On Chip
AP Flash
FFH
256 byte On Chip
AUX RAM
00H
0000H
0000H
FFFH
0000H
4K byte On Chip
LD ROM
Figure 8- 1 Memory Map
8.1 Program Memory (on-chip Flash)
The Program Memory on the W78E516D/W78E058D series can be up to 64K/32K bytes long. All in-
structions are fetched for execution from this memory area. The MOVC instruction can also access
this memory region.
8.2 Scratch-pad RAM and Register Map
As mentioned before the W78E516D/W78E058D series have separate Program and Data Memory
areas. There are also several Special Function Registers (SFRs) which can be accessed by software.
The SFRs can be accessed only by direct addressing, while the on-chip RAM can be accessed by
either direct or indirect addressing.
FFH
Indirect
RAM
Addressing
80H
7FH
Direct
&
Indirect
RAM
00H
Addressing
SFR
Direct
Addressing
Only
256 bytes RAM and SFR Data Memory Space
Figure 8- 2 W78E516D/W78E058D RAM and SFR Memory Map
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