Special Function Register (Sfr) Addressing - NEC PD789488 User Manual

3.4.3 Special function register (SFR) addressing

[Function]
The memory-mapped special function registers (SFRs) are addressed with 8-bit immediate data in an
instruction word.
This addressing is applied to the 256-byte space FF00H to FFFFH. However, the SFRs mapped at FF00H to
FF1FH can also be accessed with short direct addressing.
[Operand format]
Identifier
sfr
[Description example]
MOV PM0, A; When selecting PM0 for sfr
[Illustration]
7
15
Effective
1 1
Address
CHAPTER 3 CPU ARCHITECTURE
Description
Special function register name
Instruction code
0
OP code
sfr-offset
8 7
1 1 1 1 1 1
User's Manual U15331EJ4V1UD
1 1 1 0 0 1 1
0 0 1 0 0 0 0
0
1
0
SFR
71