Samsung S3F80JB manual BCP Bit Compare, Bcp, Operation

Models: S3F80JB

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INSTRUCTION SETS3F80JB

BCP — Bit Compare

BCP

dst,src.b

Operation:

dst(0) – src(b)

 

The specified bit of the source is compared to (subtracted from) bit zero (LSB) of the destination.

 

The zero flag is set if the bits are the same; otherwise it is cleared. The contents of both

 

operands are unaffected by the comparison.

Flags:

C: Unaffected.

 

Z:

Set if the two bits are the same; cleared otherwise.

 

S:

Cleared to "0".

 

V:

Undefined.

 

D:

Unaffected.

 

H:

Unaffected.

Format:

 

 

 

Bytes Cycles

Opcode

Addr Mode

 

(Hex)

dst

src

opc

dst b 0

src

3

6

17

r0

Rb

NOTE: In the second byte of the instruction format, the destination address is four bits, the bit address 'b' is three bits, and the LSB address value is one bit in length.

Example: Given: R1 = 07H and register 01H = 01H:

BCP R1,01H.1

R1 = 07H, register 01H = 01H

If destination working register R1 contains the value 07H (00000111B) and the source register 01H contains the value 01H (00000001B), the statement "BCP R1,01H.1" compares bit one of the source register (01H) and bit zero of the destination register (R1). Because the bit values are not identical, the zero flag bit (Z) is cleared in the FLAGS register (0D5H).

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Page 146
Image 146
Samsung S3F80JB manual BCP Bit Compare, Bcp, Operation