PIC18F2420/2520/4420/4520
INFSNZ
Increment f, Skip if Not 0
INCFSZ
Increment f, Skip if 0
Syntax:
INFSNZ f {,d {,a}}
Syntax:
INCFSZ f {,d {,a}}
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operands:
0 ≤ f ≤ 255
d ∈ [0,1]
a ∈ [0,1]
Operation:
(f) + 1→ dest,
skip if result ≠ 0
Operation:
(f) + 1→ dest,
skip if result = 0
Status Affected:
Encoding:
None
Status Affected:
Encoding:
None
0100
10da
ffff
ffff
0011
11da
ffff
ffff
Description:
The contents of register ‘f’ are
Description:
The contents of register ‘f’ are
incremented. If ‘d’ is ‘0’, the result is
placed in W. 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 NOPis executed
instead, making it a two-cycle
incremented. If ‘d’ is ‘0’, the result is
placed in W. If ‘d’ is ‘1’, the result is
placed back in register ‘f’ (default).
If the result is ‘0’, the next instruction,
which is already fetched, is discarded
and a NOPis executed instead, making
it a two-cycle instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
instruction.
If ‘a’ is ‘0’, the Access Bank is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 24.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f ≤ 95 (5Fh). See
Section 24.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
Words:
Cycles:
1
Words:
Cycles:
1
1(2)
1(2)
Note: 3 cycles if skip and followed
by a 2-word instruction.
Note: 3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Q Cycle Activity:
Q1
Q2
Q3
Q4
Q2
Q3
Q4
Decode
Read
register ‘f’
Process
Data
Write to
destination
Decode
Read
register ‘f’
Process
Data
Write to
destination
If skip:
Q1
If skip:
Q1
Q2
Q3
Q4
Q2
Q3
Q4
No
No
No
No
No
No
No
No
operation
operation
operation
operation
operation
operation
operation
operation
If skip and followed by 2-word instruction:
If skip and followed by 2-word instruction:
Q1
Q2
Q3
Q4
Q1
Q2
Q3
Q4
No
No
No
No
No
No
No
No
operation
operation
operation
operation
operation
operation
operation
operation
No
No
No
No
No
No
No
No
operation
operation
operation
operation
operation
operation
operation
operation
Example:
HERE
NZERO
ZERO
INCFSZ
:
:
CNT, 1, 0
Example:
HERE
ZERO
NZERO
INFSNZ REG, 1, 0
Before Instruction
PC
After Instruction
Before Instruction
PC
After Instruction
=
Address (HERE)
=
Address (HERE)
REG
If REG
PC
If REG
PC
=
REG + 1
0;
Address (NZERO)
0;
Address (ZERO)
CNT
If CNT
PC
If CNT
PC
=
CNT + 1
≠
=
=
=
=
=
≠
=
0;
Address (ZERO)
0;
Address (NZERO)
© 2008 Microchip Technology Inc.
DS39631E-page 289