PIC18F2420 MICROCHIP [Microchip Technology], PIC18F2420 Datasheet - Page 288

• Manufacturer Part Number: PIC18F2420
• Description: 28/40/44-Pin Enhanced Flash Microcontrollers with 10-Bit A/D and nanoWatt Technology
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18F2420/2520/4420/4520
DAW
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Example1:
Example 2:
DS39631A-page 286
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
DAW
None
If [W<3:0> > 9] or [DC = 1] then
(W<3:0>) + 6
else
(
If [W<7:4> + DC > 9] or [C = 1] then
(
else
(W<7:4>) + DC
C
DAW adjusts the eight-bit value in W,
resulting from the earlier addition 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 + DC
Read
0000
Q2
A5h
0
0
05h
1
0
CEh
0
0
34h
1
0
0000
W<3:0>;
Process
Data
W<3:0>;
Q3
W<7:4>
0000
W<7:4> ;
Write
Q4
W
0111
Preliminary
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
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 is selected.
If ‘a’ is ‘1’, the BSR is used to select the
GPR bank (default).
If ‘a’ is ‘0’ and the extended instruction
set is enabled, this instruction operates
in Indexed Literal Offset Addressing
mode whenever f
Section 24.2.3 “Byte-Oriented and
Bit-Oriented Instructions in Indexed
Literal Offset Mode” for details.
1
1
DECF
Read
0000
Q2
01h
0
00h
1
f
[0,1]
[0,1]
 2004 Microchip Technology Inc.
255
dest
CNT,
01da
Process
Data
Q3
95 (5Fh). See
1, 0
ffff
destination
Write to
Q4
ffff