test44x_ca01.c

来自「iar开发环境 msp430单片机的一些示例程序 有adc flash lcd 」· C语言 代码 · 共 54 行

//*******************************************************************************
//  MSP430-TEST44X Demo - Comp_A Output Comparator_A reference voltages on P1.6
//
//  Description; Output comparator_A reference levels on P1.6.  Program will 
//  cycle through the on-chip comparator_A reference voltages with output on 
//  P1.6. Normal mode is LPM0, TA0_ISR will interrupt LPM0.
//  ACLK = n/a, MCLK = SMCLK = default DCO ~ 800kHz
//
//		  MSP430F449
//             -----------------
//         /|\|              XIN|-  
//          | |                 |
//          --|RST          XOUT|-
//            |                 |
//            |             P1.6|-->Vref
//            |                 |			 
//
//  Yang Rui
//  Lierda, Inc
//  MAY 2004
//  Built with IAR Embedded Workbench Version: 1.26B
//******************************************************************************

#include  "msp430x11x1.h"

void delay(void);                       // Software delay

void main (void)
{
  WDTCTL = WDTPW + WDTHOLD;             // Stop WDT
  CACTL2 = P2CA0;                       // P2.3 = +comp
  CCTL0 = CCIE;                         // CCR0 interrupt enabled
  TACTL = TASSEL_2 + ID_3 + MC_2;       // SMCLK/8, cont-mode
  _EINT();                              // enable interrupts

  while (1)                             // Loop
  {
    CACTL1 = 0x00;                      // No reference voltage
    _BIS_SR(LPM0_bits);                 // Enter LPM0
    CACTL1 = CAREF0 + CAON;             // 0.25*Vcc on P2.3, Comp. on
    _BIS_SR(LPM0_bits);                 // Enter LPM0
    CACTL1 = CAREF1 + CAON;             // 0.5*Vcc on P2.3, Comp. on
    _BIS_SR(LPM0_bits);                 // Enter LPM0
    CACTL1 = CAREF1 + CAREF0 + CAON;    // 0.55V on P2.3, Comp. on
    _BIS_SR(LPM0_bits);                 // Enter LPM0
  }
}

// Timer A0 interrupt service routine
interrupt[TIMERA0_VECTOR] void Timer_A(void)
{
    _BIC_SR_IRQ(LPM0_bits);             // Clear LPM0 bits from 0(SR)
}