Texas Instruments MSP430x1xx User Manual

Page 83

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Instruction Set Overview

5-19

16-Bit CPU

5.3.2

Single-Operand Instructions

Figure 5–8 illustrates the single-operand instruction format.

Figure 5–8. Single Operand Instruction Format

B/W

D/S-Reg

15

0

Opcode

8

7

14

13

12

11

10

9

6

5

4

3

2

1

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Table 5–16 describes the effects of an instruction on the single operand
instruction status bits.

Table 5–16.Single Operand Instruction Format Results

Mnemonic

S-Reg, D-Reg

Operation

Status Bits

V

N

Z

C

RRC

dst

C –> MSB –>.......LSB –> C

*

*

*

*

RRA

dst

MSB –> MSB –>....LSB –> C

0

*

*

*

PUSH

src

SP – 2 –> SP, src –> @ SP

SWPB

dst

swap bytes

CALL

dst

SP – 2 –> SP

PC+2 –> stack, dst –> PC

RETI

TOS –> SR, SP <– SP + 2

X

X

X

X

TOS –> PC, SP <– SP + 2

SXT

dst

Bit 7 –> Bit 8........Bit 15

0

*

*

*

*

The status bit is affected

The status bit is not affected

0

The status bit is cleared

1

The status bit is set

All addressing modes are possible for the CALL instruction. If the symbolic
mode (ADDRESS), the immediate mode (#N), the absolute mode (&EDE) or
the indexed mode X (RN) is used, the word that follows contains the address
information.

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