msp430x24x_compa_04.s43

步进电机驱动程序msp430f247单片机

;******************************************************************************
;   MSP430x24x Demo - Comparator A, Poll input CA0, result in P1.0
;
;   Description: The voltage at pin CA0 (Vcompare) is compared with reference
;   voltage of diode ref.  LED is toggled when Vcompare crosses the ref voltage.
;
;                 MSP430F249
;             -----------------
;         /|\|                 |
;          | |                 |
;          --|RST      P2.3/CA0|<--Vcompare
;            |                 |
;            |       P1.0/CAOUT|-->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

            mov.b   #CAON+CAREF_3+CARSEL, &CACTL1  ;Enable comp, ref = Diode ref
            mov.b   #P2CA0, &CACTL2         ; Pin to CA0

SetupP1     bis.b   #BIT0,&P1DIR            ; P1.0 = output direction
            bis.b   #BIT0,&P1SEL            ; P1.0 = CAOUT

;-----------------------------------------------------------------------------
            COMMON  INTVEC                  ; Interrupt Vectors
;-----------------------------------------------------------------------------
            ORG     RESET_VECTOR            ; RESET Vector
            DW      RESET                   ;
            END