msp430x11x1_nmi.asm

MSP430X11x1 Assembler Examples Code,Composer Essentials Code Examples

;*******************************************************************************
;   MSP430x11x1 Demo - Basic Clock, Configure RST/NMI as NMI
;
;   Description: Configure RST/NMI as NMI, hi/lo edge. Flash P1.0  inside of
;   NMI_ISR if NMI occurs. General enable interrupt in status register does
;   not need to be .set for NMI. NMIIE does need to be reset, as NMI_ISR
;   automatically clears NMI enable to prevent unintentional stack overflow
;   that could result from, bounce or uncontrolled NMI's.
;   ACLK = n/a, MCLK = SMCLK = DCO ~800k
;
;                MSP430F1121
;             -----------------
;         /|\|              XIN|-
;          | |                 |
;          --|RST          XOUT|-
;            |                 |
;
;   M. Buccini / Z. Albus
;   Texas Instruments Inc.
;   May 2005
;   Built with Code Composer Essentials Version: 1.0
;*******************************************************************************
 .cdecls C,LIST,  "msp430x11x1.h"
;-------------------------------------------------------------------------------
            .text                           ;
;-------------------------------------------------------------------------------
RESET       mov.w   #300h,SP                ; Initialize stackpointer
SetupWDT    mov.w   #WDTPW+WDTHOLD+WDTNMI+WDTNMIES,&WDTCTL  ; WDT off NMI hi/lo
            bis.b   #01h,&P1DIR             ; P1.0 = output
            bic.b   #01h,&P1OUT             ; P1.0 = reset
            bis.b   #NMIIE,&IE1             ; Enable NMI
                                            ;
Mainloop    jmp     Mainloop                ; Endless Loop
                                            ;
;-------------------------------------------------------------------------------
NMI_ISR   ; Flash P1.0
;-------------------------------------------------------------------------------
            bis.b   #01h,&P1OUT             ; P1.0 = .set
Wait        push.w  #020000                 ; Delay value --> TOS
Wait1       dec.w   0(SP)                   ; Decrement TOS
            jnz	    Wait1                   ; Delay over?
            incd.w  SP                      ; Clean up stack
            bic.b   #01h,&P1OUT             ; P1.0 = reset
            bic.b   #NMIIFG,&IFG1           ; reclear NMI flag in case bounce
            bis.b   #NMIIE,&IE1             ; Re-enable NMI interrupt
            reti                            ; Done
                                            ;
;-------------------------------------------------------------------------------
;           Interrupt Vectors
;-------------------------------------------------------------------------------
            .sect   ".int14"                ; NMI vector
            .short  NMI_ISR                 ;
            .sect   ".reset"                ; MSP430 RESET Vector
            .short  RESET                   ;
            .end