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//******************************************************************************
// MSP430F22x4 Demo - Timer_A, PWM TA1-2, Up/Down Mode, 32kHz ACLK
//
// Description: This program generates two PWM outputs on P1.2,3 using
// Timer_A configured for up/down mode. The value in TACCR0, 128, defines the
// PWM period/2 and the values in TACCR1 and TACCR2 the PWM duty cycles. Using
// 32kHz ACLK as TACLK, the timer period is 7.8ms with a 75% duty cycle on
// P1.2 and 25% on P1.3. Normal operating mode is LPM3.
// ACLK = TACLK = LFXT1 = 32768Hz, MCLK = default DCO ~1.2MHz
// //* External watch crystal on XIN XOUT is required for ACLK *//
//
// MSP430F22x4
// -----------------
// /|\| XIN|-
// | | | 32kHz
// --|RST XOUT|-
// | |
// | P1.2/TA1|--> TACCR1 - 75% PWM
// | P1.3/TA2|--> TACCR2 - 25% PWM
//
// A. Dannenberg
// Texas Instruments Inc.
// April 2006
// Built with CCE Version: 3.2.0 and IAR Embedded Workbench Version: 3.41A
//******************************************************************************
#include "msp430x22x4.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
TACCR0 = 128; // PWM Period/2
TACCTL1 = OUTMOD_6; // TACCR1 toggle/set
TACCR1 = 32; // TACCR1 PWM duty cycle
TACCTL2 = OUTMOD_6; // TACCR2 toggle/set
TACCR2 = 96; // TACCR2 PWM duty cycle
TACTL = TASSEL_1 + MC_3; // ACLK, up-down mode
__bis_SR_register(LPM3_bits); // Enter LPM3
}
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