mc68hc08az60 Freescale Semiconductor, Inc, mc68hc08az60 Datasheet - Page 69

• Manufacturer Part Number: mc68hc08az60
• Description: M68hc08 Family Of 8-bit Microcontroller Units Mcus
• Manufacturer: Freescale Semiconductor, Inc

Program counter
(PC)
Condition code
register (CCR)
5-cpu
MOTOROLA
NOTE:
CCR
PC
Reset:
Read:
Write:
Reset:
Read:
Write:
The location of the stack is arbitrary and may be relocated anywhere in
RAM. Moving the SP out of page zero ($0000 to $00FF) frees direct
address (page zero) space. For correct operation, the stack pointer must
point only to RAM locations.
The program counter is a 16-bit register that contains the address of the
next instruction or operand to be fetched.
Normally, the program counter automatically increments to the next
sequential memory location every time an instruction or operand is
fetched. Jump, branch, and interrupt operations load the program
counter with an address other than that of the next sequential location.
During reset, the program counter is loaded with the reset vector
address located at $FFFE and $FFFF. The vector address is the
address of the first instruction to be executed after exiting the reset state.
The 8-bit condition code register contains the interrupt mask and five
flags that indicate the results of the instruction just executed. Bits 6 and
5 are set permanently to ‘1’. The following paragraphs describe the
functions of the condition code register.
Freescale Semiconductor, Inc.
X = Indeterminate
For More Information On This Product,
Bit
15
Bit 7
V
X
Figure 6. Condition code register (CCR)
14
Central Processor Unit (CPU)
Go to: www.freescale.com
13
Figure 5. Program counter (PC)
6
1
1
12
Loaded with vector from $FFFE and $FFFF
11
5
1
1
10
9
H
X
4
8
7
3
1
I
6
Central Processor Unit (CPU)
MC68HC08AZ60 — Rev 1.0
5
N
X
2
4
3
X
1
Z
CPU registers
2
1
Bit 0
C
X
Bit
0
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