This thread has been locked.

If you have a related question, please click the "Ask a related question" button in the top right corner. The newly created question will be automatically linked to this question.

msp430g2553上用定时器输出两路频率、占空比可调的方波

Other Parts Discussed in Thread: MSP430G2553

如何在msp430g2553上用定时器输出两路频率、占空比可调的方波?求源码,如果有已有的例程更好,谢谢!

  • 官网例程里没有两路的。一路pwm输出的好像也没有可调频率、占空比的。不过很简单的,下面例程调节CCR0和CCR1就能调整频率和占空比。一路会了,两路就简单了。 

    //******************************************************************************
    //  MSP430G2xx3 Demo - Timer_A, PWM TA1, Up/Down Mode, 32kHz ACLK
    //
    //  Description: This program generates one PWM output on P1.2 using
    //  Timer_A configured for up/down mode. The value in CCR0, 128, defines the
    //  PWM period/2 and the value in CCR1 the PWM duty cycle. Using
    //  32kHz ACLK as TACLK, the timer period is 7.8ms with a 75% duty cycle on
    //  P1.2. Normal operating mode is LPM3.
    //  ACLK = TACLK = LFXT1 = 32768Hz, MCLK = default DCO
    //  //* External watch crystal installed on XIN XOUT is required for ACLK *//	
    //
    //               MSP430G2xx3
    //            -----------------
    //        /|\|              XIN|-
    //         | |                 | 32kHz
    //         --|RST          XOUT|-
    //           |                 |
    //           |         P1.2/TA1|--> CCR1 - 75% PWM
    //
    //  D. Dang
    //  Texas Instruments, Inc
    //  December 2010
    //   Built with CCS Version 4.2.0 and IAR Embedded Workbench Version: 5.10
    //******************************************************************************
    
    #include <msp430.h>
    
    int 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
      CCR0 = 128;                               // PWM Period/2
      CCTL1 = OUTMOD_6;                         // CCR1 toggle/set
      CCR1 = 32;                                // CCR1 PWM duty cycle
      TACTL = TASSEL_1 + MC_3;                  // ACLK, up-down mode
    
      __bis_SR_register(LPM3_bits);             // Enter LPM3
    }