PIC18F010/020
INCFSZ
Increment f, skip if 0
Syntax:
[ label ] INCFSZ f [ ,d [,a] ]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) + 1 → dest,
skip if result = 0
Status Affected: None
Encoding:
0011 11da ffff ffff
Description:
The contents of register ’f’ are
incremented. If ’d’ is 0, the result is
placed in WREG. If ’d’ is 1, the
result is placed back in register ’f’
(default).
If the result is 0, the next instruc-
tion, which is already fetched, is
discarded, and a NOP is executed
instead making it a two-cycle
instruction. If ’a’ is 0, the Access
Bank will be selected, overriding
the BSR value. If ’a’ is 1, the Bank
will be selected as per the BSR
value.
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Q2
Q3
Decode
Read
register ’f’
Process
Data
If skip:
Q1
Q2
Q3
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q4
Write to
destination
Q4
No
operation
Q1
No
operation
No
operation
Q2
No
operation
No
operation
Q3
No
operation
No
operation
Q4
No
operation
No
operation
Example:
HERE INCFSZ CNT
NZERO :
ZERO :
Before Instruction
PC
= Address (HERE)
After Instruction
CNT =
If CNT =
PC =
If CNT ≠
PC =
CNT + 1
0;
Address(ZERO)
0;
Address(NZERO)
INFSNZ
Increment f, skip if not 0
Syntax:
[label] INFSNZ f [, d [,a] ]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) + 1 → dest,
skip if result ≠ 0
Status Affected: None
Encoding:
0100 10da ffff ffff
Description:
The contents of register 'f' are
incremented. If 'd' is 0, the result is
placed in WREG. If 'd' is 1, the
result is placed back in register 'f'
(default).
If the result is not 0, the next
instruction, which is already
fetched, is discarded, and a NOP is
executed instead making it a two-
cycle instruction. If ’a’ is 0, the
Access Bank will be selected, over-
riding the BSR value. If ’a’ is 1, the
Bank will be selected as per the
BSR value.
Words:
1
Cycles:
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Q2
Q3
Q4
Decode
Read
register ’f’
Process
Data
Write to
destination
If skip:
Q1
Q2
Q3
Q4
No
operation
No
operation
No
operation
No
operation
If skip and followed by 2-word instruction:
Q1
No
operation
No
operation
Q2
No
operation
No
operation
Q3
No
operation
No
operation
Q4
No
operation
No
operation
Example:
HERE
ZERO
NZERO
INFSNZ REG
Before Instruction
PC
= Address (HERE)
After Instruction
REG =
If REG ≠
PC =
If REG =
PC =
REG + 1
0;
Address (NZERO)
0;
Address (ZERO)
2001 Microchip Technology Inc.
Preliminary
DS41142A-page 117