Back
//******************************************************************************
// MSP430F21x2 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.
//
// MSP430F21x2
// -----------------
// /|\| XIN|-
// | | |
// --|RST XOUT|-
// | |
// |A10 P1.0|-->LED
//
// A. Dannenberg
// Texas Instruments Inc.
// December 2007
// Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.41A
//******************************************************************************
#include "msp430x21x2.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=TIMER0_A0_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)
}
|