61
CHAPTER 3 CPU ARCHITECTURE
User’s Manual U15104EJ2V0UD
3.4.2 Register addressing
[Function]
This addressing mode is used to access a general-purpose register as an operand. The register to be accessed
is specified by the register bank select flags (RBS0 and RBS1) and the register specification codes (Rn and RPn)
in the operation code.
Register addressing is carried out when an instruction with the following operand format is executed. When an
8-bit register is specified, one of the eight registers is specified with 3 bits in the operation code.
[Operand format]
Symbol
Description
r
X, A, C, B, E, D, L, H
rp
AX, BC, DE, HL
'r' and 'rp' can be written with function names (X, A, C, B, E, D, L, H, AX, BC, DE, and HL) as well as absolute
names (R0 to R7 and RP0 to RP3).
[Example]
MOV A, C; when selecting C register as r
Operation code
0 1 1 0 0 0 1 0
Register specification code
INCW DE; when selecting DE register pair as rp
Operation code
1 0 0 0 0 1 0 0
Register specification code
Содержание mPD178053
Страница 2: ...2 User s Manual U15104EJ2V0UD MEMO ...