NEC 78K/0 Series - Manual (Page 28)

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CHAPTER 3 ADDRESSING
User's Manual U12326EJ4V0UM
15 0
SFR
Effective
address
1 1 1 1 1 1 1
8 7
0 7
OP code
sfr-offset
1
3.2.5 Special-function register (SFR) addressing
[Function]
A memory-mapped special function register (SFR) is addressed with 8-bit immediate data in an instruction
word.
This addressing is applied to the 240-byte spaces FF00H to FFCFH and FFE0H to FFFFH. However, the
SFRs mapped at FF00H to FF1FH can be accessed with short direct addressing.
[Operand format]
Identifier Description
sfr Special function register name
sfrp 16-bit-manipulatable special function register name (even address only)
[Description example]
MOV PM0, A; When selecting PM0 for sfr
[Illustration]
Instruction code 1 1 1 1 0 1 1 0 OP code
0 0 1 0 0 0 0 0 20H (sfr-offset)