
2004 Microchip Technology Inc.
Preliminary
DS39637A-page 379
PIC18F2480/2580/4480/4580
CPFSGT
Example:
CPFSLT
Example:
Compare f with W, Skip if f > W
Syntax:
Operands:
CPFSGT f {,a}
0
≤
f
≤
255
a
∈
[0,1]
(f)
(
W),
skip if (f) > (W)
(unsigned comparison)
None
Operation:
Status Affected:
Encoding:
Description:
0110
Compares the contents of data memory
location ‘f’ to the contents of the W by
performing an unsigned subtraction.
If the contents of ‘f’ are greater than the
contents of WREG
,
then the fetched
instruction is discarded and a
NOP
is
executed instead, making this a
two-cycle instruction.
If ‘a(chǎn)’ is ‘
0
’, the Access Bank is selected.
If ‘a(chǎn)’ is ‘
1
’, the BSR is used to select the
GPR bank (default).
If ‘a(chǎn)’ is ‘
0
’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f
≤
95 (5Fh). See
Section 25.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode”
for details.
1
1(2)
Note:
3 cycles if skip and followed
by a 2-word instruction.
010a
ffff
ffff
Words:
Cycles:
Q Cycle Activity:
Q1
Q2
Q3
Q4
No
Decode
Read
register ‘f’
Process
Data
operation
If skip:
Q1
No
Q2
No
Q3
No
Q4
No
operation
operation
operation
operation
If skip and followed by 2-word instruction:
Q1
No
operation
operation
No
operation
operation
Q2
No
Q3
No
Q4
No
operation
No
operation
operation
No
operation
No
HERE CPFSGT REG, 0
NGREATER :
GREATER :
Before Instruction
PC
W
After Instruction
If REG
=
=
Address
(HERE)
>
=
≤
=
W;
Address
(GREATER)
W;
Address
(NGREATER)
PC
If REG
PC
Compare f with W, Skip if f < W
Syntax:
CPFSLT f {,a}
Operands:
0
≤
f
≤
255
a
∈
[0,1]
(f) –
(
W),
skip if (f) < (W)
(unsigned comparison)
Operation:
Status Affected:
None
Encoding:
0110
000a
ffff
ffff
Description:
Compares the contents of data memory
location ‘f’ to the contents of W by
performing an unsigned subtraction.
If the contents of ‘f’ are less than the
contents of W, then the fetched
instruction is discarded and a
NOP
is
executed instead, making this a
two-cycle instruction.
If ‘a(chǎn)’ is ‘
0
’, the Access Bank is selected.
If ‘a(chǎn)’ is ‘
1
’, the BSR is used to select the
GPR bank (default).
Words:
1
Cycles:
1(2)
Note:
3 cycles if skip and followed
by a 2-word instruction.
Q Cycle Activity:
Q1
Q2
Q3
Q4
No
Decode
Read
register ‘f’
Process
Data
operation
If skip:
Q1
No
Q2
No
Q3
No
Q4
No
operation
operation
operation
operation
If skip and followed by 2-word instruction:
Q1
No
operation
operation
No
operation
operation
Q2
No
Q3
No
Q4
No
operation
No
operation
operation
No
operation
No
HERE CPFSLT REG, 1
NLESS :
LESS :
Before Instruction
PC
W
After Instruction
If REG
PC
If REG
PC
=
=
Address
(HERE)
<
=
≥
=
W;
Address
(LESS)
W;
Address
(NLESS)