INSTRUCTION SET

S3C84E5/C84E9/P84E9

 

 

RLC — Rotate Left through Carry

RLCdst

Operation: dst (0) C

C dst (7)

dst (n + 1) dst (n), n = 0–6

The contents of the destination operand with the carry flag are rotated left one bit position. The initial value of bit 7 replaces the carry flag (C), and the initial value of the carry flag replaces bit zero.

7

0

C

 

Flags:

C: Set if the bit rotated from the most significant bit position (bit 7) was "1".

Z:Set if the result is "0"; cleared otherwise.

S:Set if the result bit 7 is set; cleared otherwise.

V:Set if arithmetic overflow occurred, that is, if the sign of the destination is changed during the rotation; cleared otherwise.

D:Unaffected.

H:Unaffected.

Format:

Bytes Cycles Opcode

Addr Mode

(Hex)

dst

opc

dst

2

4

10

R

 

4

11

IR

Examples:

Given:

Register 00H

= 0AAH, register 01H = 02H, and register 02H =

17H, C =

"0":

 

RLC

00H

Register 00H

=

54H, C = "1"

 

 

 

RLC

@01H

Register 01H

=

02H, register 02H

= 2EH, C

= "0"

In the first example, if the general register 00H has the value 0AAH (10101010B), the statement "RLC 00H" rotates 0AAH one bit position to the left. The initial value of bit 7 sets the carry flag and the initial value of the C flag replaces bit zero of the register 00H, leaving the value 55H (01010101B). The MSB of the register 00H resets the carry flag to "1" and sets the overflow flag.

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Samsung S3C84E5 user manual RLC Rotate Left through Carry, RLCdst Operation dst 0 ← C, 00H Register 00H 54H, C =