msp430用ADC10求平均值

只看该作者 · 2012-3-20 23:27

#include "msp430f2122.h"

unsigned char key_value();
void main( void )
{
  // Stop watchdog timer to prevent time out reset
  WDTCTL = WDTPW + WDTHOLD;

  while(1)
  {
P1DIR |=0X80;
key_value();
}

}

unsigned char key_value()
{ unsigned char i,ad_value=0;
  ADC10CTL0 = SREF_1+REFON+REF2_5V+ADC10SHT_2 + ADC10ON;
  ADC10CTL1 = INCH_7+CONSEQ_2;
  ADC10AE0 |= 0x80;
  P1DIR |= 0x01;
  ADC10CTL0 |= ENC+ADC10SC;
  if (ADC10MEM*2.5/1023<2)
  {
P1OUT |=0X80;
for(i=0;i<4;i++)
{
   ADC10CTL0 |= ENC+ADC10SC;
   while (ADC10CTL1 & ADC10BUSY);
   ad_value=ad_value+ADC10MEM;
}
ad_value=ad_value/4;
  if(ad_value*2.5/1023>0.2)
P1OUT |=0X01;
  else
P1OUT &=~0X01;
  }
return ad_value;
}