PWM Timer 1 output for CC2530

Thank You for Your fast answer.Code that You wrote works perfectly :)

Another question..If I want to send pwm out at the same time on Port P0_2,P0_3,P0_4 and P0_5 what should I do? How to write code for that?

You then have to use several Timer 1 channels. Do you want the same or different PWM signals? Note that since P0_2 is controlled by Channel 0, it has limited PWM possibilities, because it is also the timer period, meaning that it is difficult to get anything other than 50% duty cycle. So you should consider to use P0_6 instead of P0_2.

Each of the channels need to be set up similar to channel 1. The pins have to be selected as peripheral using P0SEL. (P0SEL |= 0x3C; to use P0_2-P05, P0SEL |= 0x78 to use P0_3-P0_6.) In order to get priority for all the Timer 1 pins, you will need to move both UART0 and UART1 to Alternative 2 location, i.e. PERCFG |= 0x03;.

In my project it's used p0_2 to P0_5...For now I use the same pwm signal for all ports.But If it isn't difficult to You toi explain to me how to write code with same PWM on every port and different PWM.Tnakn You

Thank You again for Your fast answer. But code that You send me doesn't works.What Do you think what is wrong? If I need more advise I ask You :)

Thank You :)...Code is working and as You said on Port P0_2 duty cycle is 50%..I need 25% duty cycle so I know how that to change and how to play with.Thank You again vry much for helping me and fast answers.If I wuold have so questions I ask.

I have one more question. With this code T1CTL |= 0x0f I selected to work in up down mode and 32Mhz I divide with 128 so I get 250kHz..My question is how to select that pwm signal is working on 50kHz frequency?

Sorry for my late answer,thank You for your quick answer again, my LED's works fine :)

I have another question. I need that duty cycle change automatically. For exaple to be at first 10% after 2second 20 % and that goes until gets 90%.Afterwords it goes to decrease duty cycle on same duty cycles but in different course. And to do that all the time to increase and decrease duty cycle. I hope that You can help me.Thanks

To do this, you need to set up an interrupt and let that interrupt update the duty cycle (update the T1CCnL/T1CCnH). One option is to set up an overflow interrupt on Timer 1. You will then get an interrupt for each period of the signal. You can update a counter in that ISR and change the duty cycle when the counter expires. The disadvantage of this solution is that you will get interrupts more frequently than strictly needed.

Another way  is to use a different timer to time the updates. The best options are the sleep timer or Timer 2. The sleep timer uses a different clock source, so the duty cycle updates will not be synchronous to the PWM. You should be careful about using Timer 2, as it is normally used for the radio (e.g. if you are using Z-stack, RemoTI, TIMAC, or SimpliciTI). However, if that timer is free, it is long enough to generate interrupts every 2 seconds.

In SampleAPP i wrote this but it doesn't work,what I do wrong:

 if ( events & TOGGLE_TIMER_EVENT )
  {
   
    static int togle = 0;
    static short T1CC1 = 0x0240;
  
       if (togle == 0 && T1CC1 > 0x0020)
    {
      T1CC1 += 20;
   
    } else {
      togle = 1;
      }
  
     if (togle == 1 && T1CC1 < 0x0240)
    {
      T1CC1 = T1CC1 + 20;
   
    } else {
      togle = 0;
      }
      
        
    osal_start_timerEx( SampleApp_TaskID, TOGGLE_TIMER_EVENT , 2000);
      
 
    // return unprocessed events
    return (events ^ TOGGLE_TIMER_EVENT);
  }
  // Discard unknown events
  return 0;
}

I want to PWM starts from 10% and go to 90% and then backwords

I have not worked with PWM using Timer1 so I hesitate to comment on your use of the T1CC1 register except: your static short T1CC1 = 0x0240; statement is working on a static variable that has the same name as the timer register -- probably not what you intended.

Which Timer You used and how do You solved that PWM is changing Duty cycle from exaple from 10% to 90%?

Hi,

    How can I modify code if I want  to output PWM signal on P1.3? Thanks.

Have a look in the User's Guide chapter 7.

/Fredrik

I am using following code to get timer signal at P0_3.   It is working OK.

But it takes 2ms for 1 time ON and 1 time OFF.  I need  that it will take 2ms for 5 times ON and 5 times OFF.

For better understanding I have attached file.

PERCFG  &= ~0x40;                 //select Timer  1 Alternative at Port 0 Location                                                                        
PERCFG  |=  0x03;                 //Move USART0 and USART1 to Alternative 2 Location                                                                        
P2DIR   = (P2DIR & ~0xC0) | 0X80; //Give priority to Timer 1                                                                        
P0SEL   |=  0x08;                 // SET P0_3 AS PERIPHERAL                                                                        
T1CC0L  = 0xFF;           //PWM signal period                                                           
T1CC0H  = 0x7F;                                                                        
T1CC1L  = 0x00;         //PWM Duty Cycle, Channel 1 (P0_3)                                                                        
T1CC1H  = 0x01;                                                                        
T1CCTL1 = 0x34;         //Channel 1 in compare Mode, Set output on Compare down,                                                                     
T1CTL |= 0x01;        //Start the timer in free running Mode

Waiting for beneficial reply.

Thanks6012.5824.TIMER SPEED.xls

Hi All,

This is Karthik and i am being working on cc2530ZDK now and i need to generate the four different pwm signals at the same time at four different GPIO ..I am posting the code below

#define MAX_PWM_VAL 2047

 /* setup P1.0 as PWM output of CCR channel 2 */
  PERCFG |= 0x40; // T1CFG = 1: Timer 1 Alternative 2 location
  P1DIR |= 0x01; // P1.0 set to output
  P1SEL |= 0x01; // set P1.0 to peripheral function

  /* setup timer module */
  T1CC0H = HI_UINT16(MAX_PWM_VAL);
  T1CC0L = LO_UINT16(MAX_PWM_VAL);
  T1CTL |= 0x06 ; // 0000 01 10 -> 32MHz/8 = 4MHz, mode=modulo
  T1CCTL2 = 0x34; // 00 110 1 00 -> no interrupt, ch 2 compare = 6, compare mode, no capture

#ifdef ZDO_COORDINATOR
  // set ADC module reference
  HalAdcSetReference(HAL_ADC_REF_AVDD);  
#endif

//NEXT FUNCTION

  UINT16 pwm_value;

 pwm_value = brightness * (MAX_PWM_VAL / 100);
 
  // set the new PWM value
  T1CC2H = HI_UINT16(pwm_value);
  T1CC2L = LO_UINT16(pwm_value);
}

As Mentioned above P1.0 is been used to generate the pwm signal using timer 1.It is Successful and i am able to see the output at IO_LED1 (Green LED) that is p1.0

Similarly i am doing it for P1.1 and P1.4 but i am unable to generate the pwm signal .

I would like to have some detailed information regarding this issue.

Expecting the solution asap,

Advance Thanks for the help

Regards,

KARTHIK V

i have a 16 bit values from 20 to 30 and i have to use pwm to control the speed of a dc motor .. i am using cc2530dk kit .. the problem is i am not able to find the function for using the pwm and i have no idea ... any comments pl 

Hi Dhileep,

Have you looked at the user guide I linked to in my previous post? Everything you need to know about the timers is described there.

Cheers,
Fredrik

i couldnt find it sir !!! i needed to control the duty cycle with the digital values i have from 20 to 30 

Ok, I see that my original link is dead. Here is it again: http://www.ti.com/lit/pdf/swru191

Have a look in chapters 9 and 10.