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//*******************************************************************************
// MSP430x47xx Demo - Timer_A, PWM TA1-2 Up Mode, 32kHz ACLK
//
// Description: This program outputs two PWM signals on P1.2 and P2.0
// using Timer_A configured for up mode. The value in CCR0 defines the PWM
// period and the values in CCR1 and CCR2 the PWM duty cycles. Using 32kHz
// ACLK as TACLK, the timer period is 15.6ms with a 75% duty cycle on P1.2
// and 25% on P2.0. Normal operating mode is LPM3.
// ACLK = LFXT1 = 32768Hz, MCLK = SMCLK = default DCO = 32 x ACLK = 1048576Hz
// //* An external watch crystal between XIN & XOUT is required for ACLK *//
//
// MSP430x47xx
// -----------------
// /|\| XIN|-
// | | | 32kHz
// --|RST XOUT|-
// | |
// | P1.2/TA1|--> CCR1 - 75% PWM
// | P2.0/TA2|--> CCR2 - 25% PWM
//
// P. Thanigai / K.Venkat
// Texas Instruments Inc.
// November 2007
// Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.42A
//*****************************************************************************
#include <msp430x47x4.h>
void main(void)
{
WDTCTL = WDTPW +WDTHOLD; // Stop WDT
FLL_CTL0 |= XCAP14PF; // Configure load caps
P1DIR |= BIT2; // P1.2 output
P1SEL |= BIT2; // P1.2 TA1 option
P2DIR |= BIT0; // P2.0 output
P2SEL |= BIT0; // P2.0 TA2 option
CCR0 = 512-1; // PWM Period
CCTL1 = OUTMOD_7; // CCR1 reset/set
CCR1 = 384; // CCR1 PWM duty cycle
CCTL2 = OUTMOD_7; // CCR2 reset/set
CCR2 = 128; // CCR2 PWM duty cycle
TACTL = TASSEL_1 + MC_1; // ACLK, up mode
_BIS_SR(LPM3_bits); // Enter LPM3
}
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