PIC18F2331_07 Datasheet, PDF (309/400 Pages) Microchip Technology – 28/40/44-Pin Enhanced Flash Microcontrollers with nanoWatt Technology, High Performance PWM and A/D

PIC18F2331/2431/4331/4431
CPFSGT
Compare f with W, Skip if f > W
Syntax:
[ label ] CPFSGT f [,a]
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operation:
(f) − (W),
skip if (f) > (W)
(unsigned comparison)
Status Affected:
None
Encoding:
0110 010a ffff ffff
Description:
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’ is ‘0’, the Access
Bank will be selected, overriding the
BSR value. If ‘a’ = 1, then the bank will
be selected as per the BSR value
(default).
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:
Q1
Q2
Q3
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Q4
No
operation
Q4
No
operation
Q4
No
operation
No
operation
Example:
HERE
CPFSGT REG
NGREATER :
GREATER :
Before Instruction
PC
=
W
=
Address (HERE)
?
After Instruction
If REG
PC
If REG
PC
> W;
= Address (GREATER)
≤ W;
= Address (NGREATER)
CPFSLT
Compare f with W, Skip if f < W
Syntax:
[ label ] CPFSLT f [,a]
Operands:
0 ≤ f ≤ 255
a ∈ [0,1]
Operation:
(f) – (W),
skip if (f) < (W)
(unsigned comparison)
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’ is ‘0’, the
Access Bank will be selected. If ‘a’ is ‘1’,
the BSR will not be overridden (default).
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:
Q1
Q2
Q3
No
operation
No
operation
No
operation
No
operation
No
operation
No
operation
Q4
No
operation
Q4
No
operation
Q4
No
operation
No
operation
Example:
HERE
NLESS
LESS
CPFSLT REG
:
:
Before Instruction
PC
=
W
=
Address (HERE)
?
After Instruction
If REG
PC
If REG
PC
< W;
= Address (LESS)
≥ W;
= Address (NLESS)
© 2007 Microchip Technology Inc.
Preliminary
DS39616C-page 307