BCLR

Clearing a bit

BCLR

Bit CLeaR


[Syntax]

BCLR src, dest

 

[Operation]

When dest is a memory location:

unsigned char dest;

dest &= ~( 1 << ( src & 7 ));

 

When dest is a register:

register unsigned long dest;

dest &= ~( 1 << ( src & 31 ));

[Function]

-

This instruction clears the bit of dest, which is specified by src.

-

The immediate value given as src is the number (position) of the bit.

-

The range for IMM:3 operands is 0 ? IMM:3 ? 7. The range for IMM:5 is 0 ? IMM:5 ? 31.

 

[Instruction Format]

Syntax

Processng Size

src

src2

dest

Code size

(Byte)

(1)BCLR src, dest

B

#IMM:3

-

[Rd].B

2

B

#IMM:3

-

dsp:8[Rd].B

3

B

#IMM:3

-

dsp:16[Rd].B

4

B

Rs

-

[Rd].B

3

B

Rs

-

dsp:8[Rd].B

4

B

Rs

-

dsp:16[Rd].B

5

(2)BCLR src, dest

L

#IMM:5

-

Rd

2

L

Rs

-

Rd

3

[Flag Change]

This instruction does not affect the states of flags.

[Description Example]

BCLR #7, [R2]

BCLR R1, [R2]

BCLR #31, R2

BCLR R1, R2