PIC18F258-I/SP View Datasheet(PDF) - Microchip Technology

Part Name

Description

Manufacturer

PIC18F258-I/SP

28/40-Pin High-Performance, Enhanced Flash Microcontrollers with CAN Module

Microchip Technology 

PIC18FXX8

DAW

Syntax:

Operands:

Operation:

Decimal Adjust W Register

[ label ] DAW

None

If [W<3:0> > 9] or [DC = 1] then

(W<3:0>) + 6 → W<3:0>;

else

(W<3:0>) → W<3:0>

If [W<7:4> > 9] or [C = 1] then

(W<7:4>) + 6 → W<7:4>;

else

(W<7:4>) → W<7:4>

Status Affected: C

Encoding:

0000 0000 0000 0111

Description:

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.

Words:

1

Cycles:

1

Q Cycle Activity:

Q1

Decode

Example 1:

Q2

Read

register W

DAW

Q3

Process

Data

Q4

Write

W

Before Instruction

W

=

C

=

DC

=

After Instruction

W

=

C

=

DC

=

Example 2:

0xA5

0

0

0x05

1

0

Before Instruction

W

=

C

=

DC

=

After Instruction

W

=

C

=

DC

=

0xCE

0

0

0x34

1

0

DECF

Syntax:

Operands:

Operation:

Status Affected:

Encoding:

Description:

Words:

Cycles:

Q Cycle Activity:

Q1

Decode

Decrement f

[ label ] DECF f [,d [,a]]

0 ≤ f ≤ 255

d ∈ [0,1]

a ∈ [0,1]

(f) – 1 → dest

C, DC, N, OV, Z

0000 01da ffff ffff

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

Q2

Read

register ‘f’

Q3

Process

Data

Q4

Write to

destination

Example:

DECF CNT,

Before Instruction

CNT =

Z

=

After Instruction

CNT =

Z

=

0x01

0

0x00

1

DS41159E-page 300

© 2006 Microchip Technology Inc.

Share Link: