• State
  • Locked Locked
  • Replies 2 replies
  • Subscribers 78 subscribers
  • Views 924 views
  • Users 0 members are here
Support feedback
Options
Options
Similar topics

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.

FREQUENCY CAPTURE IN MSP430G2152

Ashok kumar Karnan
Prodigy 110 points
Other Parts Discussed in Thread: MSP430G2152

Hi Guys;

        I am using msp430g2152 for my project application in that i want to capture 840khz  frequency signal..... by using 16mhz  oscillator signal... i cant able to capture my signal so help me..

 ADVANCE THANKS TO ALL

This is my code

TACTL = TASSEL_2 +MC_2;                         
TACCTL1 = CM_1+CCIS_0+SCS+CAP+CCIE;

840khz exact  count value is 19 but instead of that i got 39 or 59 or40 so please help me to capture that signal...

  • 0
    TI__Mastermind 26380 points

    Hello,

    We may need more information before we can determine what the problem is - esp the clock settings/ port setting.

    In any case I have a simple example on the F20xx that captures a 1KHz signal using a 1MHz clock source.

    Compare it to your to see if you are missing anything...

    Regards,

    Priya

  • 0 in reply to Priya Thanigai
    Prodigy 110 points

    Hello Priya,

      

    0383.capture.txt 
    #include <msp430g2152.h>					
unsigned int new_cap=0;						
unsigned int old_cap=0;						
unsigned int cap_diff=0;					
void main(void)
{
    WDTCTL = WDTPW + WDTHOLD;                   		// Stop WDT
    BCSCTL1 = CALBC1_16MHZ;                    // Set Oscillator range
  DCOCTL = CALDCO_16MHZ; 
    P1SEL |= BIT2;                              		// Port 1.2/TACCR1 - Input                 
   P1DIR=0xF0;				        		// P1.4, P1.5, P1.6, P1.7 as a output
    P1OUT=0x00; 						// Initially reset port1                     
  P1OUT |=0x10;						// P1.4 High for Green status LED 
    TACTL = TASSEL_2 +MC_2;          				// SMCLK = 1 Mhz, continuous mode
    TACCTL1 = CM_1+CCIS_0+SCS+CAP+CCIE; 			// capture on rising edge & falling edge, Timer A select, Sync., capture mode, Enable timer interrupt
        
    __bis_SR_register(LPM0_bits + GIE);         		// LPM0 mode
}    

// Timer A1 interrupt service routine

#pragma vector = TIMER0_A1_VECTOR
__interrupt void TA1_ISR(void)
{
 switch( TAIV )                                 // Efficient switch-implementation
  {
    case 2:                                     // CCR1 capture value
      new_cap = TACCR1;
    cap_diff = new_cap - old_cap;		
     old_cap = new_cap;                          // move current value 
   break;                 
  }
}
    6014.capture.txt 
    #include <msp430g2152.h>					
unsigned int new_cap=0;						
unsigned int old_cap=0;						
unsigned int cap_diff=0;					
void main(void)
{
    WDTCTL = WDTPW + WDTHOLD;                   		// Stop WDT
    BCSCTL1 = CALBC1_16MHZ;                    // Set Oscillator range
  DCOCTL = CALDCO_16MHZ; 
    P1SEL |= BIT2;                              		// Port 1.2/TACCR1 - Input                 
   P1DIR=0xF0;				        		// P1.4, P1.5, P1.6, P1.7 as a output
    P1OUT=0x00; 						// Initially reset port1                     
  P1OUT |=0x10;						// P1.4 High for Green status LED 
    TACTL = TASSEL_2 +MC_2;          				// SMCLK = 1 Mhz, continuous mode
    TACCTL1 = CM_1+CCIS_0+SCS+CAP+CCIE; 			// capture on rising edge & falling edge, Timer A select, Sync., capture mode, Enable timer interrupt
        
    __bis_SR_register(LPM0_bits + GIE);         		// LPM0 mode
}    

// Timer A1 interrupt service routine

#pragma vector = TIMER0_A1_VECTOR
__interrupt void TA1_ISR(void)
{
 switch( TAIV )                                 // Efficient switch-implementation
  {
    case 2:                                     // CCR1 capture value
      new_cap = TACCR1;
    cap_diff = new_cap - old_cap;		
     old_cap = new_cap;                          // move current value 
   break;                 
  }
}

     I attached my coding....my aim is to capture above 840khz frequency by using 16mhz internal clock oscillator in msp430g2152 controller....so please refer my code and reply

    Thanks in advance

**Attention** This is a public forum