Timer_A has been configured for 10-bit PWM mode.. // TACCR1 duty cycle is automatically proportional to ADC10 A0.. WDT_ISR used // as a period wakeup timer approximately 45ms based on de
Trang 1//****************************************************************************** // MSP430G2x31 Demo - ADC10, DTC Sample A0 -> TA1, AVcc, DCO
//
// Description: Use DTC to sample A0 with reference to AVcc and directly
// transfer code to TACCR1 Timer_A has been configured for 10-bit PWM mode // TACCR1 duty cycle is automatically proportional to ADC10 A0 WDT_ISR used // as a period wakeup timer approximately 45ms based on default ~1.2MHz
// DCO/SMCLK clock source used in this example for the WDT clock source
// Timer_A also uses default DCO
//
// MSP430G2x31
//
-// /|\|
XIN|-// | | |
// |RST
XOUT|-// | |
// > -|P1.0/A0 P1.2| > TACCR1 - 0-1024 PWM
//
// D Dang
// Texas Instruments Inc
// October 2010
// Built with CCS Version 4.2.0 and IAR Embedded Workbench Version: 5.10
//******************************************************************************
#include "msp430g2231.h"
void main(void)
{
WDTCTL = WDT_MDLY_32; // WDT ~45ms interval timer
IE1 |= WDTIE; // Enable WDT interrupt
ADC10CTL0 = ADC10SHT_2 + ADC10ON;
ADC10AE0 |= 0x01; // P1.0 ADC option select
ADC10DTC1 = 0x001; // 1 conversion
P1DIR |= 0x04; // P1.2 = output
P1SEL |= 0x04; // P1.2 = TA1 output
TACCR0 = 1024 - 1; // PWM Period
TACCTL1 = OUTMOD_7; // TACCR1 reset/set
TACCR1 = 512; // TACCR1 PWM Duty Cycle
TACTL = TASSEL_2 + MC_1; // SMCLK, upmode
while(1)
{
bis_SR_register(LPM0_bits + GIE); // LPM0, WDT_ISR will force exit ADC10SA = (unsigned int)&TACCR1; // Data transfer location
ADC10CTL0 |= ENC + ADC10SC; // Start sampling
}
}
#pragma vector = WDT_VECTOR
interrupt void WDT_ISR(void)
{
bic_SR_register_on_exit(LPM0_bits); // Exit LPM0
}