PIC18F24 MICROCHIP [Microchip Technology], PIC18F24 Datasheet - Page 320

• Manufacturer Part Number: PIC18F24
• Description: 28/40-Pin High-Performance, Enhanced Flash Microcontrollers with CAN Module
• Manufacturer: MICROCHIP [Microchip Technology]

SUBWFB
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example 1:
Example 2:
Example 3:
DS41159D-page 318
PIC18FXX8
Q Cycle Activity:
Before Instruction
After Instruction
Before Instruction
After Instruction
Before Instruction
After Instruction
Decode
REG
W
C
REG
W
C
Z
N
REG
W
C
REG
W
C
Z
N
REG
W
C
REG
W
C
Z
N
Q1
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
=
register ‘f’
Subtract W from f with Borrow
[ label ]
0
d
a
(f) – (W) – (C)
N, OV, C, DC, Z
Subtract W and the Carry flag (borrow)
from register ‘f’ (2’s complement
method). If ‘d’ is ‘0’, the result is stored
in W. If ‘d’ is ‘1’, the result is stored back
in register ‘f’ (default). If ‘a’ is ‘0’, the
Access Bank will be selected,
overriding the BSR value. If ‘a’ is ‘1’,
then the bank will be selected as per the
BSR value (default).
1
1
Read
SUBWFB REG, 1, 0
SUBWFB REG, 0, 0
SUBWFB REG, 1, 0
0101
Q2
f
[0,1]
[0,1]
0x19
0x0D
0x01
0x0C
0x0D
0x01
0x00
0x00
0x1B
0x1A
0x00
0x1B
0x00
0x01
0x01
0x00
0x03
0x0E
0x01
0xF5
0x0E
0x00
0x00
0x01
255
SUBWFB
10da
Process
(0001 1001)
(0000 1101)
(0000 1011)
(0000 1101)
; result is positive
(0001 1011)
(0001 1010)
(0001 1011)
; result is zero
(0000 0011)
(0000 1101)
(1111 0100)
; [2’s comp]
(0000 1101)
; result is negative
Data
Q3
dest
f [,d [,a]]
ffff
destination
Write to
Q4
ffff
SWAPF
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example:
Q Cycle Activity:
Before Instruction
After Instruction
Decode
REG
REG
Q1
=
=
register ‘f’
Swap f
[ label ]
0
d
a
(f<3:0>)
(f<7:4>)
None
The upper and lower nibbles of register
‘f’ are exchanged. If ‘d’ is ‘0’, the result
is placed in W. If ‘d’ is ‘1’, the result is
placed in register ‘f’ (default). If ‘a’ is ‘0’,
the Access Bank will be selected,
overriding the BSR value. If ‘a’ is ‘1’,
then the bank will be selected as per
the BSR value (default).
1
1
SWAPF
Read
0011
Q2
f
0x53
0x35
[0,1]
[0,1]
 2004 Microchip Technology Inc.
255
SWAPF f [,d [,a]]
REG
dest<7:4>,
dest<3:0>
10da
Process
Data
Q3
ffff
destination
Write to
Q4
ffff