msp430x20x2 adc10 08

// Vref Software writes to ADC10SC to trigger sample burst.. In Mainloop MSP430 // waits in LPM0 to save power until ADC10 conversion complete, ADC10_ISRDTC // will force exit from any L

//****************************************************************************** // MSP430F20x2 Demo - ADC10, DTC Sample A1 32x, 1.5V, Repeat Single, DCO

//

// Description: Use DTC to sample A1 32 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 any LPMx in Mainloop on reti ADC10 internal

// oscillator times sample period (16x) and conversion (13x) DTC transfers

// conversion code to RAM 200h - 240h P1.0 set at start of conversion burst,

// reset on completion

//

// MSP430F20x2

//

-// /|\|

XIN|-// | | |

// |RST

XOUT|-// | |

// > -|P1.1/A1 P1.0| >LED

//

// L Westlund

// Texas Instruments Inc

// May 2006

// Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.41A

//******************************************************************************

#include "msp430x20x2.h"

void main(void)

{

WDTCTL = WDTPW + WDTHOLD; // Stop WDT

ADC10CTL1 = CONSEQ_2+INCH_1; // Repeat single channel

ADC10CTL0 = SREF_1 + ADC10SHT_2 + MSC + REFON + ADC10ON + ADC10IE; enable_interrupt(); // Enable interrupts

TACCR0 = 30; // Delay to allow Ref to settle

TACCTL0 |= CCIE; // Compare-mode interrupt

TACTL = TASSEL_2 + MC_1; // TACLK = SMCLK, Up mode

LPM0; // Wait for delay

TACCTL0 &= ~CCIE; // Disable timer Interrupt

disable_interrupt();

ADC10DTC1 = 0x20; // 32 conversions

ADC10AE0 |= 0x02; // P1.1 ADC option select

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; // Set P1.0 LED on

ADC10CTL0 |= ENC + ADC10SC; // Sampling and conversion start bis_SR_register(CPUOFF + GIE); // LPM0, ADC10_ISR will force exit

P1OUT &= ~0x01; // Clear P1.0 LED off

}

}

// 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;

LPM0_EXIT; // Exit LPM0 on return

}