Datasheet

Rev.6.00 Oct.28.2004 page 27 of 1016
REJ09B0138-0600H
2.4 Register Configuration
2.4.1 Overview
The CPU has the internal registers shown in figure 2-4. There are two types of registers: general registers and control
registers.
T ———— I2 I1 I0EXR
76543210
PC
23 0
15 07 07 0
E0
E1
E2
E3
E4
E5
E6
E7
R0H
R1H
R2H
R3H
R4H
R5H
R6H
R7H
R0L
R1L
R2L
R3L
R4L
R5L
R6L
R7L
General Registers (Rn) and Extended Registers (En)
Control Registers (CR)
Legend:
Stack pointer
Program counter
Extended control register
Trace bit
Interrupt mask bits
Condition-code register
Interrupt mask bit
User bit or interrupt mask bit*
SP:
PC:
EXR:
T:
I2 to I0:
CCR:
I:
UI:
Note: * In the H8S/2357 Group, this bit cannot be used as an interrupt mask.
ER0
ER1
ER2
ER3
ER4
ER5
ER6
ER7 (SP)
I UI HUNZVCCCR
76543210
Half-carry flag
User bit
Negative flag
Zero flag
Overflow flag
Carry flag
H:
U:
N:
Z:
V:
C:
Figure 2-4 CPU Registers
2.4.2 General Registers
The CPU has eight 32-bit general registers. These general registers are all functionally alike and can be used as both
address registers and data registers. When a general register is used as a data register, it can be accessed as a 32-bit, 16-bit,
or 8-bit register. When the general registers are used as 32-bit registers or address registers, they are designated by the
letters ER (ER0 to ER7).
The ER registers divide into 16-bit general registers designated by the letters E (E0 to E7) and R (R0 to R7). These
registers are functionally equivalent, providing a maximum sixteen 16-bit registers. The E registers (E0 to E7) are also
referred to as extended registers.