PIC18FXX8 Datasheet, PDF (312/402 Pages) Microchip Technology – 28/40-Pin High-Performance, Enhanced Flash Microcontrollers with CAN Module

PIC18FXX8
POP
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Q Cycle Activity:
Q1
Decode
Pop Top of Return Stack
[ label ] POP
None
(TOS) → bit bucket
None
0000 0000 0000 0110
The TOS value is pulled off the return
stack and is discarded. The TOS value
then becomes the previous value that
was pushed onto the return stack.
This instruction is provided to enable
the user to properly manage the return
stack to incorporate a software stack.
1
1
Q2
No
operation
Q3
POP TOS
value
Q4
No
operation
Example:
POP
GOTO
Before Instruction
TOS
Stack (1 level down)
After Instruction
TOS
PC
NEW
= 0x0031A2
= 0x014332
= 0x014332
= NEW
PUSH
Push Top of Return Stack
Syntax:
[ label ] PUSH
Operands:
Operation:
Status Affected:
None
(PC + 2) → TOS
None
Encoding:
Description:
Words:
Cycles:
0000 0000 0000 0101
The PC + 2 is pushed onto the top of
the return stack. The previous TOS
value is pushed down on the stack.
This instruction allows the user to
implement a software stack by
modifying TOS and then pushing it onto
the return stack.
1
1
Q Cycle Activity:
Q1
Q2
Decode PUSH PC + 2
onto return
stack
Q3
No
operation
Q4
No
operation
Example:
PUSH
Before Instruction
TOS
PC
After Instruction
PC
TOS
Stack (1 level down)
= 0x00345A
= 0x000124
= 0x000126
= 0x000126
= 0x00345A
DS41159D-page 310
 2004 Microchip Technology Inc.