PIC16F57 Microchip Technology Inc., PIC16F57 Datasheet - Page 48

• Manufacturer Part Number: PIC16F57
• Description: Flash-based, 8-bit Cmos Microcontroller Series
• Manufacturer: Microchip Technology Inc.

PIC16F5X
COMF
Syntax:
Operands:
Operation:
Status Affected: Z
Encoding:
Description:
Words:
Cycles:
Example:
DECF
Syntax:
Operands:
Operation:
Status Affected: Z
Encoding:
Description:
Words:
Cycles:
Example:
DS41213D-page 46
Before Instruction
After Instruction
Before Instruction
After Instruction
REG1
REG1
W
CNT
Z
CNT
Z
Complement f
[ label ] COMF
0 ≤ f ≤ 31
d ∈ [0,1]
(f) → (dest)
The contents of register ‘f’ are
complemented. If ‘d’ is ‘0’, the
result is stored in the W register. If
‘d’ is ‘1’, the result is stored back in
register ‘f’.
1
1
COMF
Decrement f
[ label ] DECF f, d
0 ≤ f ≤ 31
d ∈ [0,1]
(f) – 1 → (dest)
Decrement register ‘f’. If ‘d’ is ‘0’,
the result is stored in the W
register. If ‘d’ is ‘1’, the result is
stored back in register ‘f’.
1
1
DECF
0010
0000
=
=
=
=
=
=
=
0x13
0x13
0xEC
0x01
0
0x00
1
REG1,0
01df
11df
CNT, 1
f, d
ffff
ffff
DECFSZ
Syntax:
Operands:
Operation:
Status Affected: None
Encoding:
Description:
Words:
Cycles:
Example:
Before Instruction
After Instruction
PC
CNT
if CNT
PC
if CNT
PC
Decrement f, Skip if 0
[ label ] DECFSZ f, d
0 ≤ f ≤ 31
d ∈ [0,1]
(f) – 1 → d;
The contents of register ‘f’ are
decremented. If ‘d’ is ‘0’, the result
is placed in the W register. If ‘d’ is
‘1’. the result is placed back in
register ‘f’. If the result is ‘0’, the
next instruction, which is already
fetched, is discarded and a NOP is
executed instead making it a
two-cycle instruction.
1
1(2)
HERE
CONTINUE •
0010
=
=
=
=
≠
=
© 2007 Microchip Technology Inc.
address(HERE)
CNT - 1;
0,
address (CONTINUE);
0,
address (HERE+1)
11df
DECFSZ
GOTO
•
•
skip if result = 0
ffff
CNT, 1
LOOP