STM8 instruction set

PM0044

BCPL

Bit Complement

BCPL

Syntax

BCPL dst, #pos (pos=0..7) e.g. BCPL PADR,#4

Operation

dst(pos) <= 1 - dst(pos)

Description

Complements the bit position in destination location. Leaves all other bits

unchanged.

M(longmem).bit <- -M(longmem).bit

Instruction overview

mnem

dst

Affected condition flags

V

I1

H

I0

N

Z

C

BCPL

Mem

-

-

-

-

-

-

-

Detailed description

dst

pos = 0..7

Asm

cy

lgth

Op-code(s)

ST7

longmem

n = 2*pos

BCPL $1000,#2

1

4

90

1n

MS

LS

82/162

Doc ID 13590 Rev 3

mnem

Affected condition flags

V

I1

H

I0

N

Z

C

SIM

-

1

-

1

-

-

-

Detailed description

Addressing

Asm

cy

lgth

Op-code(s)

ST7

mode

Inherent

BREAK

1

1

8B

Doc ID 13590 Rev 3

83/162

STM8 instruction set

PM0044

BRES

Bit Reset

BRES

Syntax

BRES dst,#pos

pos = [0..7]

e.g. BRES PADR,#6

Operation

dst <= dst AND COMPLEMENT (2**pos)

Description

Read the destination byte, reset the corresponding bit (bit position), and

write the result in destination byte. The destination is a memory byte. The

bit position is a constant. This instruction is fast, compact, and does not

affect any register. Very useful for boolean variable manipulation.

Instruction overview

mnem

dst

bit position

Affected condition flags

V

I1

H

I0

N

Z

C

BRES

Mem

#pos

-

-

-

-

-

-

-

Detailed description

dst

pos = 0..7

Asm

cy

lgth

Op-code(s)

ST7

longmem

n=1+2*pos

BRES $1000,#7

1

4

72

1n

MS

LS

84/162

Doc ID 13590 Rev 3

BSET

Bit Set

BSET

Syntax

BSET dst,#pos pos = [0..7]

e.g. BSET PADR,#7

Operation

dst <= dst OR (2**pos)

Description

Read the destination byte, set the corresponding bit (bit position), and write

the result in destination byte. The destination is a memory byte. The bit

position is a constant. This instruction is fast, compact, and does not affect

any register. Very useful for boolean variable manipulation.

mnem

dst

bit position

Affected condition flags

V

I1

H

I0

N

Z

C

BSET

Mem

#pos

-

-

-

-

-

-

-

Detailed description

dst

pos = 0..7

Asm

cy

lgth

Op-code(s)

ST7

longmem

n=2*pos

BSET $1000,#1

1

4

72

1n

MS

LS

Doc ID 13590 Rev 3

85/162