Texas Instruments MSP430x4xx User Manual

Page 88

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Instruction Set

3-54

RISC 16−Bit CPU

* POP[.W]

Pop word from stack to destination

* POP.B

Pop byte from stack to destination

Syntax

POP

dst

POP.B

dst

Operation

@SP −> temp
SP + 2 −> SP
temp −> dst

Emulation

MOV

@SP+,dst or MOV.W @SP+,dst

Emulation

MOV.B

@SP+,dst

Description

The stack location pointed to by the stack pointer (TOS) is moved to the
destination. The stack pointer is incremented by two afterwards.

Status Bits

Status bits are not affected.

Example

The contents of R7 and the status register are restored from the stack.

POP

R7

; Restore R7

POP

SR

; Restore status register

Example

The contents of RAM byte LEO is restored from the stack.

POP.B

LEO

; The low byte of the stack is moved to LEO.

Example

The contents of R7 is restored from the stack.

POP.B

R7

; The low byte of the stack is moved to R7,
; the high byte of R7 is 00h

Example

The contents of the memory pointed to by R7 and the status register are
restored from the stack.

POP.B

0(R7)

; The low byte of the stack is moved to the
; the byte which is pointed to by R7
: Example:

R7 = 203h

;

Mem(R7) = low byte of system stack

: Example:

R7 = 20Ah

;

Mem(R7) = low byte of system stack

POP

SR

; Last word on stack moved to the SR

Note:

The System Stack Pointer

The system stack pointer (SP) is always incremented by two, independent
of the byte suffix.

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