Texas Instruments MSP430x4xx User Manual

Page 95

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Instruction Set

3-61

RISC 16−Bit CPU

RRC[.W]

Rotate right through carry

RRC.B

Rotate right through carry

Syntax

RRC

dst or

RRC.W

dst

RRC

dst

Operation

C −> MSB −> MSB−1 .... LSB+1 −> LSB −> C

Description

The destination operand is shifted right one position as shown in Figure 3−17.
The carry bit (C) is shifted into the MSB, the LSB is shifted into the carry bit (C).

Figure 3−17. Destination Operand—Carry Right Shift

15

0

7

0

C

Byte

Word

Status Bits

N: Set if result is negative, reset if positive
Z: Set if result is zero, reset otherwise
C: Loaded from the LSB
V: Set if initial destination is positive and initial carry is set, otherwise reset

Mode Bits

OSCOFF, CPUOFF, and GIE are not affected.

Example

R5 is shifted right one position. The MSB is loaded with 1.

SETC

; Prepare carry for MSB

RRC

R5

; R5/2 + 8000h −> R5

Example

R5 is shifted right one position. The MSB is loaded with 1.

SETC

; Prepare carry for MSB

RRC.B

R5

; R5/2 + 80h −> R5; low byte of R5 is used

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