//****************************************************************************** // 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 - // /|\| // || | // |RST XOUT|- // // XIN|- | > -|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; LPM0; // TACLK = SMCLK, Up mode // 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; P1OUT |= 0x01; // Data buffer start // 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