;******************************************************************************* ; MSP430F20xx 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 = Default DCO ; ; MSP430F20xx ; ; /|\| XIN|; | | | ; |RST XOUT|; | | ; ; M Buccini / L Westlund ; Texas Instruments Inc ; October 2005 ; Built with IAR Embedded Workbench Version: 3.40A ;******************************************************************************* #include "msp430x20x3.h" ; ORG 0F800h ; Program Reset ; RESET mov.w #0280h,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 ; ORG 0FFFCh ; NMI vector DW NMI_ISR ; ORG 0FFFEh ; MSP430 RESET Vector DW RESET ; END