PIC17C7XX Datasheet, PDF (207/328 Pages) Microchip Technology – High-Performance 8-Bit CMOS EPROM Microcontrollers with 10-bit A/D

PIC17C7XX
CPFSEQ
Compare f with WREG,
skip if f = WREG
Syntax:
[ label ] CPFSEQ f
Operands:
0 ≤ f ≤ 255
Operation:
(f) – (WREG),
skip if (f) = (WREG)
(unsigned comparison)
Status Affected: None
Encoding:
0011 0001 ffff ffff
Description:
Compares the contents of data memory
location 'f' to the contents of WREG by
performing an unsigned subtraction.
If 'f' = WREG then the fetched instruc-
tion is discarded and an NOP is exe-
cuted instead making this a two-cycle
instruction.
Words:
1
Cycles:
1 (2)
Q Cycle Activity:
Q1
Decode
If skip:
Q1
No
operation
Q2
Read
register 'f'
Q2
No
operation
Q3
Process
Data
Q3
No
operation
Q4
No
operation
Q4
No
operation
Example:
HERE CPFSEQ REG
NEQUAL :
EQUAL :
Before Instruction
PC Address =
WREG
=
REG
=
HERE
?
?
After Instruction
If REG
=
PC
=
If REG
≠
PC
=
WREG;
Address (EQUAL)
WREG;
Address (NEQUAL)
CPFSGT
Compare f with WREG,
skip if f > WREG
Syntax:
[ label ] CPFSGT f
Operands:
0 ≤ f ≤ 255
Operation:
(f) − (WREG),
skip if (f) > (WREG)
(unsigned comparison)
Status Affected: None
Encoding:
0011 0010 ffff ffff
Description:
Compares the contents of data memory
location 'f' to the contents of the WREG
by performing an unsigned subtraction.
If the contents of 'f' are greater than the
contents of WREG then the fetched
instruction is discarded and an NOP is
executed instead making this a
two-cycle instruction.
Words:
1
Cycles:
1 (2)
Q Cycle Activity:
Q1
Decode
If skip:
Q1
No
operation
Q2
Read
register 'f'
Q2
No
operation
Q3
Process
Data
Q3
No
operation
Q4
No
operation
Q4
No
operation
Example:
HERE
CPFSGT REG
NGREATER :
GREATER :
Before Instruction
PC
=
WREG
=
Address (HERE)
?
After Instruction
If REG
>
PC
=
If REG
≤
PC
=
WREG;
Address (GREATER)
WREG;
Address (NGREATER)
© 1998 Microchip Technology Inc.
DS30289A-page 207