18F452 datasheet(230/332 Pages) MICROCHIP

230 / 332 page

PIC18FXX2

DS39564B-page 228

 2002 Microchip Technology Inc.

COMF

Complement f

Syntax:

[ label ] COMF

f [,d [,a]

Operands:

≤ f ≤ 255

∈ [0,1]

Operation:

→ dest

Status Affected:

N, Z

Encoding:

0001

11da

ffff

Description:

The contents of register ’f’ are com-

plemented. 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).

Words:

Cycles:

Q Cycle Activity:

Decode

Read

Process

Data

Write to

destination

Example:

COMF

REG,

0, 0

Before Instruction

REG

0x13

After Instruction

REG

0x13

0xEC

(f )

CPFSEQ

Compare f with W, skip if f = W

Syntax:

[ label ] CPFSEQ

f [,a]

Operands:

≤ f ≤ 255

∈ [0,1]

Operation:

(f) – (W),

skip if (f) = (W)

(unsigned comparison)

Status Affected:

None

Encoding:

0110

001a

ffff

Description:

Compares the contents of data

memory location 'f' to the contents

of W by performing an unsigned

subtraction.

If 'f' = W

, then the fetched instruc-

tion is discarded and a NOP is exe-

cuted instead, making this a two-

cycle instruction. If ‘a’ is 0, the

Access Bank will be selected, over-

riding the BSR value. If ‘a’ = 1, then

the bank will be selected as per the

BSR value (default).

Words:

Cycles:

1(2)

Note: 3 cycles if skip and followed

by a 2-word instruction.

Q Cycle Activity:

Decode

Read

Process

Data

operation

If skip:

operation

If skip and followed by 2-word instruction:

operation

Example:

HERE

CPFSEQ REG, 0

NEQUAL

EQUAL

Before Instruction

PC Address

HERE

REG

After Instruction

If REG

Address (EQUAL)

If REG

≠

Address (NEQUAL)

18F452 Datasheet(PDF) 230 Page - Microchip Technology

18F452 Datasheet(HTML) 230 Page - Microchip Technology

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL