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//******************************************************************************
// MSP430F21x2 Demo - Timer0_A3, PWM TA0_0 - TA0_2, Up Mode, 32kHz ACLK
//
// Description: This program generates two PWM outputs on P1.2,3 using
// Timer0_A3 configured for up mode. The value in TA0CCR0, 512-1, defines the PWM
// period and the values in TA0CCR1 and TA0CCR2 the PWM duty cycles. Using 32kHz
// ACLK as TA0CLK, the timer period is 15.6ms with a 75% duty cycle on P1.2
// and 25% on P1.3. Normal operating mode is LPM3.
// ACLK = TA0CLK = LFXT1 = 32768Hz, MCLK = SMCLK = default DCO ~1.2MHz
// //* External watch crystal on XIN XOUT is required for ACLK *//
//
// MSP430F21x2
// -----------------
// /|\| XIN|-
// | | | 32kHz
// --|RST XOUT|-
// | |
// | P1.2/TA0_1|--> TA0CCR1 - 75% PWM
// | P1.3/TA0_2|--> TA0CCR2 - 25% PWM
//
// A. Dannenberg
// Texas Instruments Inc.
// January 2008
// 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
P1DIR |= 0x0C; // P1.2 and P1.3 output
P1SEL |= 0x0C; // P1.2 and P1.3 TA1/2 otions
TA0CCR0 = 512 - 1; // PWM Period
TA0CCTL1 = OUTMOD_7; // TA0CCR1 reset/set
TA0CCR1 = 384; // TA0CCR1 PWM duty cycle
TA0CCTL2 = OUTMOD_7; // TA0CCR2 reset/set
TA0CCR2 = 128; // TA0CCR2 PWM duty cycle
TA0CTL = TASSEL_1 + MC_1; // ACLK, up mode
__bis_SR_register(LPM3_bits); // Enter LPM3
}
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