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//******************************************************************************
//  MSP430F22x4 Demo - ADC10, DTC Sample A10 64x, 1.5V, Repeat Single, DCO
//
//  Description: Use DTC to sample A10 64 times with reference to internal 1.5v.
//  Vref Software writes to ADC10SC to trigger sample burst. In Mainloop MSP430
//  waits in LPM0 to save power until ADC10 conversion complete, ADC10_ISR(DTC)
//  will force exit from LPM0 in Mainloop on reti. (ADC10OSC/4)/64
//  determines sample time which needs to be greater than 30us for temperature
//  sensor. DTC transfers conversion code to RAM 200h - 280h. P1.0 set at start
//  of conversion burst, reset oncompletion. Temperature sensor offset and slope
//  will vary from device to device per datasheet tolerance.
//
//                MSP430F22x4
//             -----------------
//         /|\|              XIN|-
//          | |                 |
//          --|RST          XOUT|-
//            |                 |
//            |A10          P1.0|-->LED
//
//  A. Dannenberg
//  Texas Instruments Inc.
//  October 2006
//  Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.41A
//******************************************************************************
#include "msp430x22x4.h"

void main(void)
{
  WDTCTL = WDTPW + WDTHOLD;                 // Stop WDT
  ADC10CTL1 = INCH_10 + ADC10DIV_3 + CONSEQ_2;
  ADC10CTL0 = SREF_1 + ADC10SHT_3 + MSC + REFON + ADC10ON + ADC10IE;
  TACCR0 = 30;                              // Delay to allow Ref to settle
  TACCTL0 |= CCIE;                          // Compare-mode interrupt
  TACTL = TASSEL_2 + MC_1;                  // TACLK = SMCLK, Up mode
  __bis_SR_register(CPUOFF + GIE);          // LPM0, TA0_ISR will force exit
  TACCTL0 &= ~CCIE;                         // Disable timer Interrupt
  ADC10DTC1 = 0x40;                         // 64 conversions
  P1DIR |= 0x01;                            // Set P1.0 output

  for (;;)
  {
    ADC10CTL0 &= ~ENC;                      //
    while (ADC10CTL1 & BUSY);               // Wait if ADC10 core is active
    ADC10SA = 0x200;                        // Data buffer start
    P1OUT |= 0x01;                          // P1.0 = 1
    ADC10CTL0 |= ENC + ADC10SC;             // Sampling and conversion start
    __bis_SR_register(CPUOFF + GIE);        // LPM0, ADC10_ISR will force exit
    P1OUT &= ~0x01;                         // P1.0 = 0
  }
}

// ADC10 interrupt service routine
#pragma vector=ADC10_VECTOR
__interrupt void ADC10_ISR(void)
{
  __bic_SR_register_on_exit(CPUOFF);        // Clear CPUOFF bit from 0(SR)
}

#pragma vector=TIMERA0_VECTOR
__interrupt void TA0_ISR(void)
{
  TACTL = 0;                                // Clear Timer_A control registers
  __bic_SR_register_on_exit(CPUOFF);        // Clear CPUOFF bit from 0(SR)
}