UPD78F9500MA-CAC-A Datasheet, PDF (41/342 Pages) Renesas Technology Corp – 8-Bit Single-Chip Microcontrollers

CHAPTER 3 CPU ARCHITECTURE
3.2.2 General-purpose registers
A general-purpose register consists of eight 8-bit registers (X, A, C, B, E, D, L, and H).
In addition each register being used as an 8-bit register, two 8-bit registers in pairs can be used as a 16-bit register
(AX, BC, DE, and HL).
Registers can be described in terms of function names (X, A, C, B, E, D, L, H, AX, BC, DE, and HL) and absolute
names (R0 to R7 and RP0 to RP3).
Figure 3-12. General-Purpose Register Configuration
(a) Function names
16-bit processing
HL
DE
BC
AX
15
0
8-bit processing
H
L
D
E
B
C
A
X
7
0
(b) Absolute names
16-bit processing
RP3
8-bit processing
R7
R6
RP2
RP1
RP0
15
0
R5
R4
R3
R2
R1
R0
7
0
User’s Manual U18172EJ3V0UD
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