msp430x24x_svs_01.s43

来自「步进电机驱动程序msp430f247单片机」· S43 代码 · 共 47 行

;******************************************************************************
;   MSP430x24x Demo - SVS, POR @ 2.5V Vcc
;
;   Description: The SVS POR feature is used to disable normal operation that
;   toggles P1.0 by xor'ing P1.0 inside of a software loop.
;   In the example, when VCC is above 2.5V, the MSP430 toggles P1.0. When VCC is
;   below 2.5V, the SVS resets the MSP430, and no toggle is seen.
;   ACLK= n/a, MCLK= SMCLK= default DCO ~ 1.045MHz
;
;                 MSP430x24x
;              -----------------
;          /|\|              XIN|-
;           | |                 |
;           --|RST          XOUT|-
;             |                 |
;             |             P1.0|-->LED
;
;   B. Nisarga
;   Texas Instruments Inc.
;   September 2007
;   Built with IAR Embedded Workbench Version: 3.42A
;******************************************************************************
#include  <msp430x24x.h>
;-------------------------------------------------------------------------------
            RSEG    CSTACK                  ; Define stack segment
;-------------------------------------------------------------------------------
            RSEG    CODE                    ; Assemble to Flash memory
;-------------------------------------------------------------------------------
RESET       mov.w   #SFE(CSTACK),SP         ; Initialize stackpointer
StopWDT     mov.w   #WDTPW+WDTHOLD,&WDTCTL  ; Stop WDT
SetupP1     bis.b   #001h,&P1DIR            ; P1.0  output
            mov.b   #060h+PORON,&SVSCTL     ; SVS POR enabled @ 2.5V
                                            ;
Mainloop    mov.w   #050000,R15             ; Delay to R15
L1          dec.w   R15                     ; Decrement R15
            jnz     L1                      ; Delay over?
            xor.b   #001h,&P1OUT            ; Toggle P1.0
            jmp     Mainloop                ; Again
                                            ;
;-------------------------------------------------------------------------------
            COMMON  INTVEC                  ; Interrupt Vectors
;-------------------------------------------------------------------------------
            ORG     RESET_VECTOR            ; POR, ext. Reset
            DW      RESET
            END