MPD789426 Datasheet, PDF (55/321 Pages) NEC – 8-Bit Single-Chip Microcontrollers

CHAPTER 3 CPU ARCHITECTURE
3.1.4 Data memory addressing
The µPD789426, 789436, 789446, and 789456 Subseries are provided with a variety of addressing modes to
make memory manipulation as efficient as possible. At the addresses corresponding to data memory area (FD00H
to FFFFH) especially, specific addressing modes that correspond to the particular function an area, such as the
special function registers are available. Figures 3-7 through 3-12 show the data memory addressing modes.
Figure 3-7. Data Memory Addressing (µPD789425, 789435)
FFFFH
FF20H
FF1FH
FF00H
FEFFH
Special function registers (SFRs)
256 × 8 bits
SFR addressing
Internal high-speed RAM
512 × 8 bits
Short direct
addressing
FE20H
FE1FH
FD00H
FCFFH
FA05H
FA04H
FA00H
F9FFH
3000H
2FFFH
Reserved
LCD display RAM
5 × 4 bits
Reserved
Direct adressing
Register indirect
addressing
Based addressing
0000H
Internal ROM
12288 × 8 bits
User’s Manual U15075EJ1V0UM00
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