fet440_adc12_04.c

是MSP430X44X的各部分的子程序模块

//******************************************************************************
//  MSP-FET430P440 Demo - ADC12, Using the Internal Reference
//
//  This example shows how to use the internal reference of the ADC12.
//  It uses the internal 2.5V reference and performs a single conversion
//  on channel A0. The conversion results are stored in ADC12MEM0. Test by 
//  applying a voltage to channel A0, then setting and running to a break point
//  at the "_NOP()" instruction. To view the conversion results, open an SFR 
//  window in C-Spy and view the contents of ADC12MEM0.
//
//
//                MSP430F449
//             ---------------
//            |               |
//            |      A0 (P6.0)|<---- Vin
//            |               |
//
//
//   M.Mitchell
//   Texas Instruments, Inc
//   February, 2002
//  Built with IAR Embedded Workbench Version: 1.25A
//******************************************************************************
#include          "msp430x44x.h"        // Standard Equations

void main(void)
{ 
  unsigned int i;
  WDTCTL = WDTPW+WDTHOLD;               // Stop watchdog timer
  P6SEL |= 0x01;                        // Enable A/D channel A0
  ADC12CTL0 = ADC12ON+SHT0_2+REFON+REF2_5V;  // Turn on and set up ADC12
  ADC12CTL1 = SHP;                      // Use sampling timer
  ADC12MCTL0 = SREF_1;                  // Vr+=Vref+

  for ( i=0; i<0x3600; i++)              // Delay for reference start-up
  {
  }

  ADC12CTL0 |= ENC;                     // Enable conversions

  while (1)
  { 
    ADC12CTL0 |= ADC12SC;               // Start conversion
    while ((ADC12IFG & BIT0)==0);
    _NOP();                             // SET BREAKPOINT HERE
  }                           
}