msp430x11x1_wdt_01.asm

MSP430X11x1 Assembler Examples Code,Composer Essentials Code Examples

;*******************************************************************************
;   MSP430x11x1 Demo - WDT, Toggle P1.0, Interval Overflow ISR, DCO SMCLK
;
;   Description: Toggle P1.0 using software timed by the WDT ISR. Toggle rate
;   is approximately 30ms based on default ~800kHz DCO/SMCLK clock source
;   used in this example for the WDT.
;   ACLK = n/a, MCLK = SMCLK = default DCO ~800kHz
;
;		         MSP430F1121
;             -----------------
;         /|\|              XIN|-
;          | |                 |
;          --|RST          XOUT|-
;            |                 |
;            |             P1.0|-->LED
;
;   M. Buccini / Z. Albus
;   Texas Instruments Inc.
;   May 2005
;   Built with Code Composer Essentials Version: 1.0
;*******************************************************************************
 .cdecls C,LIST,  "msp430x11x1.h"
;-------------------------------------------------------------------------------
            .text                           ; Program Start
;-------------------------------------------------------------------------------
RESET       mov.w   #300h,SP                ; Initialize stackpointer
SetupWDT    mov.w   #WDT_MDLY_32,&WDTCTL    ; WDT ~30ms interval timer
            bis.b   #WDTIE,&IE1             ; Enable WDT interrupt
SetupP1     bis.b   #001h,&P1DIR            ; P1.0 output
                                            ;						
Mainloop    bis.w   #CPUOFF+GIE,SR          ; CPU off, enable interrupts
            nop                             ; Required only for debugger
                                            ;
;-------------------------------------------------------------------------------
WDT_ISR;    Toggle P1.0
;-------------------------------------------------------------------------------
            xor.b   #001h,&P1OUT            ; Toggle P1.0
            reti                            ;		
                                            ;
;-------------------------------------------------------------------------------
;           Interrupt Vectors
;-------------------------------------------------------------------------------
            .sect   ".reset"                ; MSP430 RESET Vector
            .short  RESET                   ;
            .sect   ".int10"                ; WDT Vector
            .short  WDT_ISR                 ;
            .end