
PIC17C4X
DS30412C-page 130
1996 Microchip Technology Inc.
NEGW
Negate W
Syntax:
[
label]
NEGW
f,s
Operands:
0
≤ F ≤ 255
s
∈ [0,1]
Operation:
WREG + 1
→ (f);
WREG + 1
→ s
Status Affected:
OV, C, DC, Z
Encoding:
0010
110s
ffff
Description:
WREG is negated using two’s comple-
ment. If 's' is 0 the result is placed in
WREG and data memory location 'f'. If
's' is 1 the result is placed only in data
memory location 'f'.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register 'f'
Execute
Write
register 'f'
and other
specied
register
Example:
NEGW
REG,0
Before Instruction
WREG
=
0011 1010
[0x3A],
REG
=
1010 1011
[0xAB]
After Instruction
WREG
=
1100 0111
[0xC6]
REG
=
1100 0111
[0xC6]
NOP
No Operation
Syntax:
[
label ]
NOP
Operands:
None
Operation:
No operation
Status Affected:
None
Encoding:
0000
Description:
No operation.
Words:
1
Cycles:
1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
NOP
Execute
NOP
Example:
None.