MCMC68HC05L16 Freescale Semiconductor, Inc, MCMC68HC05L16 Datasheet - Page 35

• Manufacturer Part Number: MCMC68HC05L16
• Description: M68hc05 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Chapter 3
Central Processor Unit (CPU)
3.1 Introduction
This section describes the central processor unit (CPU).
3.2 CPU Registers
The MCU contains five registers as shown in
Figure
Freescale Semiconductor
3-2.
NOTE:
15
15
0
INCREASING
ADDRESSES
MEMORY
0
0
Since the stack pointer decrements during pushes, the PCL is stacked first,
followed by PCH, etc. Pulling from the stack is in the reverse order.
UNSTACK
0
MC68HC05L16 • MC68HC705L16 Data Sheet, Rev. 4.1
0
R
U
R
N
E
T
0
Figure 3-1. Programming Model
7
1
0
Figure 3-2. Stacking Order
1
0
PC
1
7
7
7
1
INDEX REGISTER
ACCUMULATOR
Figure
1
PCH
PCL
CONDITION CODE
3-1. The interrupt stacking order is shown in
REGISTER
H
X
A
I
SP
CCR
N
Z
0
C
0
0
0
0
N
T
E
R
R
U
P
T
I
STACK
ACCUMULATOR
INDEX REGISTER
PROGRAM COUNTER
STACK POINTER
CONDITION CODE
REGISTER
DECREASING
ADDRESSES
MEMORY
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