CM68HC05C4ACFB Motorola / Freescale Semiconductor, CM68HC05C4ACFB Datasheet - Page 32

• Manufacturer Part Number: CM68HC05C4ACFB
• Description: Microcontroller
• Manufacturer: Motorola / Freescale Semiconductor

Central Processor Unit (CPU)
3.3.1 Accumulator
3.3.2 Index Register
General Release Specification
32
The accumulator (A) shown in
register used to hold operands and results of arithmetic calculations or
data manipulations.
The index register (X) is an 8-bit register used by the indexed addressing
value to create an effective address. The index register also may be
used as a temporary storage area.
NOTE: Since the stack pointer decrements during pushes, the PCL is stacked first,
12
12
0
INCREASING
ADDRESSES
0
MEMORY
followed by PCH, etc. Pulling from the stack is in the reverse order.
Central Processor Unit (CPU)
0
UNSTACK
0
Figure 3-1. Programming Model
0
U
R
N
R
E
T
Figure 3-2. Stacking Order
7
7
7
7
1
1
PC
1
1
1
Figure 3-1
INDEX REGISTER
ACCUMULATOR
H
CONDITION CODE REGISTER
A
X
PCH
PCL
I
SP
CCR
N
is a general-purpose 8-bit
Z
C
0
0
0
0
MC68HC05C4A
0
ACCUMULATOR
INDEX REGISTER
PROGRAM COUNTER
STACK POINTER
CONDITION CODE REGISTER
N
E
R
R
U
P
T
T
I
STACK
DECREASING
ADDRESSES
MEMORY
MOTOROLA
—
Rev. 4.0