MC68HC08AZ0 Datasheet, PDF (71/444 Pages) Motorola, Inc – Advance Information

Freescale Semiconductor, Inc.
Central Processor Unit (CPU)
CPU registers
CPU registers
Figure 1 shows the five CPU registers. CPU registers are not part of the
memory map.
15
H
15
15
7
0
ACCUMULATOR (A)
0
X
INDEX REGISTER (H:X)
0
STACK POINTER (SP)
0
PROGRAM COUNTER (PC)
7
0
V 1 1 H I N Z C CONDITION CODE REGISTER (CCR)
CARRY/BORROW FLAG
ZERO FLAG
NEGATIVE FLAG
INTERRUPT MASK
HALF-CARRY FLAG
TWO’S COMPLEMENT OVERFLOW FLAG
Figure 1. CPU registers
Accumulator (A)
The accumulator is a general-purpose 8-bit register. The CPU uses the
accumulator to hold operands and the results of arithmetic/logic
operations.
Bit 7
Read:
A
Write:
Reset:
6
5
4
3
2
Unaffected by reset
Figure 1. Accumulator (A)
1
Bit 0
3-cpu
MOTOROLA
Central Processor Unit (CPU)
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MC68HC08AZ0
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