PIC18F258 MICROCHIP [Microchip Technology], PIC18F258 Datasheet - Page 298

• Manufacturer Part Number: PIC18F258
• Description: High Performance, 28/40-Pin Enhanced FLASH Microcontrollers with CAN
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18FXX8
DAW
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example1:
Example 2:
DS41159B-page 296
Q Cycle Activity:
Before Instruction
After Instruction
Before Instruction
After Instruction
Decode
W
C
DC
W
C
DC
W
C
DC
W
C
DC
Q1
=
=
=
=
=
=
=
=
=
=
=
=
register W
Decimal Adjust W Register
[label] DAW
None
If [W<3:0> >9] or [DC = 1] then
(W<3:0>) + 6
else
(
If [W<7:4> >9] or [C = 1] then
(
else
(W<7:4>)
C
DAW adjusts the eight-bit value in
W, resulting from the earlier addi-
tion of two variables (each in
packed BCD format) and produces
a correct packed BCD result.
1
1
DAW
W<3:0>)
W<7:4>) + 6
Read
0000
Q2
0xA5
0
0
0x05
1
0
0xCE
0
0
0x34
1
0
0000
Process
W<7:4>;
W<3:0>;
Data
Q3
W<3:0>;
W<7:4>;
0000
Write
Q4
W
0111
DECF
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example:
Q Cycle Activity:
Before Instruction
After Instruction
Decode
CNT
Z
CNT
Z
Q1
=
=
=
=
register ’f’
Decrement f
[ label ] DECF f [,d [,a]]
0
d
a
(f) – 1
C, DC, N, OV, Z
Decrement register 'f'. 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’ = 1, then the
bank will be selected as per the
BSR value (default).
1
1
DECF
Read
0000
Q2
0x01
0
0x00
1
f
[0,1]
[0,1]
2002 Microchip Technology Inc.
255
dest
CNT,
01da
Process
Data
Q3
ffff
destination
Write to
Q4
ffff