PIC16C62X
NOP
No Operation
[ label ] NOP
None
RETFIE
Return from Interrupt
[ label ] RETFIE
None
Syntax:
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Operands:
Operation:
No operation
None
TOS → PC,
1 → GIE
Status Affected:
Encoding:
None
00
0000
0xx0
0000
00
0000
0000
1001
No operation.
Return from Interrupt. Stack is POPed
and Top of Stack (TOS) is loaded in
the PC. Interrupts are enabled by
setting Global Interrupt Enable bit,
GIE (INTCON<7>).This is a two-cycle
instruction.
Description:
1
Cycles:
1
NOP
Example
Words:
Cycles:
Example
1
2
RETFIE
After Interrupt
PC
GIE =
=
TOS
1
RETLW
Return with Literal in W
[ label ] RETLW k
0 ≤ k ≤ 255
OPTION
Syntax:
Load Option Register
[ label ] OPTION
None
Syntax:
Operands:
Operation:
Operands:
Operation:
(W) → OPTION
k → (W);
TOS → PC
Status Affected: None
00
0000
0110
0010
Encoding:
Status Affected:
Encoding:
None
The contents of the W register are
loaded in the OPTION register. This
instruction is supported for code
compatibility with PIC16C5X products.
Since OPTION is a readable/writable
register, the user can directly
address it.
Description:
11
01xx
kkkk
kkkk
The W register is loaded with the eight
bit literal 'k'. The program counter is
loaded from the top of the stack (the
return address). This is a two-cycle
instruction.
Description:
Words:
Cycles:
Example
1
2
Words:
Cycles:
Example
1
1
CALL TABLE
;W contains table
;offset value
•
;W now has table
To maintain upward compatibility
with future PICmicro™ products,
do not use this instruction.
value
•
•
TABLE
ADDWF PC
;W = offset
;Begin table
;
RETLW k1
RETLW k2
•
•
•
RETLW kn
; End of table
Before Instruction
W
=
0x07
After Instruction
W
=
value of k8
1998 Microchip Technology Inc.
Preliminary
DS30235G-page 69
MICROCHIP [ MICROCHIP ]
