Datasheet

CHAPTER 3 CPU ARCHITECTURE
User’s Manual U18172EJ3V0UD
49
3.4.3 Special function register (SFR) addressing
[Function]
A memory-mapped special function register (SFR) is addressed with the 8-bit immediate data in an instruction
word.
This addressing is applied to the 256-byte space FF00H to FFFFH. However, SFRs mapped at FF00H to
FF1FH are accessed with short direct addressing.
[Operand format]
Identifier Description
sfr Special function register name
[Description example]
MOV PM0, A; When selecting PM0 for sfr
Instruction code 1 1 1 0 0 1 1 1
0 0 1 0 0 0 0 0
[Illustration]
15
0
SFR
Effective
address
1
111111
87
07
OP code
sfr-offset
1