PIC18C242 MICROCHIP [Microchip Technology], PIC18C242 Datasheet - Page 210

• Manufacturer Part Number: PIC18C242
• Description: High-Performance Microcontrollers with 10-Bit A/D
• Manufacturer: MICROCHIP [Microchip Technology]

PIC18CXX2
DAW
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Q Cycle Activity:
Example1:
Example 2:
DS39026B-page 210
Before Instruction
After Instruction
Before Instruction
After Instruction
Decode
WREG
C
DC
WREG
C
DC
WREG
C
DC
WREG
C
DC
Q1
=
=
=
=
=
=
=
=
=
=
=
=
Decimal Adjust WREG Register
[ label ] DAW
None
If [WREG<3:0> >9] or [DC = 1]
then
(WREG<3:0>) + 6
else
(
If [WREG<7:4> >9] or [C = 1] then
(
else
(WREG<7:4>)
C
DAW adjusts the eight bit value in
WREG resulting from the earlier
addition of two variables (each in
packed BCD format) and produces
a correct packed BCD result.
1
1
DAW
register
WREG
WREG<3:0>)
WREG<7:4>) + 6
Read
0000
Q2
0xA5
0
0
0x05
1
0
0xCE
0
0
0x34
1
0
0000
Process
Data
Q3
WREG<7:4>;
WREG<3:0>;
0000
WREG<3:0>;
WREG<7:4>;
WREG
Write
Q4
0111
Preliminary
DECF
Syntax:
Operands:
Operation:
Status Affected:
Encoding:
Description:
Words:
Cycles:
Q Cycle Activity:
Example:
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 WREG. 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]
255
7/99 Microchip Technology Inc.
dest
CNT,
01da
Process
Data
Q3
1, 0
ffff
destination
Write to
Q4
ffff