W78E054D Datasheet, PDF (14/89 Pages) List of Unclassifed Manufacturers – 8-bit microcontroller

W78E054D/W78E052D Data Sheet
8 MEMORY ORGANIZATION
The W78E054D/W78E052D 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
64K Bytes
External
Data
memory
2KB
LDROM
3FFFH
3800H
3FFFH
14K/8KB
APROM
or
16KB
APROM
0000H
Figure 8–1 Memory Map
0000H
0000H
8.1 Program Memory (on-chip Flash)
The Program Memory on the W78E054D/W78E052D series can be up to 16K/8K bytes (2K bytes for
ISP F/W, share with the W78E054D) long. All instructions 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 W78E054D/W78E052D 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.
- 14 -
Publication Release Date: Jun 9, 2015
Revision A13