Complementary PWM with Deadtime insertion

vitaliycheban — Thu, 21 Sep 2017 15:22:00 GMT

I want to run #FRDMKW41ZUG board with #MKW41Z mcu, using frdmkw41z_driver_examples_tpm_combine_pwm example with #deadtime insertion, but cannot run it well. I try to change filter register directly with no result.

You can see that no deadtime insertion.

Code from example:

#include "fsl_debug_console.h"
#include "board.h"
#include "fsl_tpm.h"

#include "pin_mux.h"
/*******************************************************************************
* Definitions
******************************************************************************/
/* define instance */
#define BOARD_TPM_BASEADDR TPM2
/* TPM channel pair 0 works with TPM channels 0 and 1*/
#define BOARD_TPM_CHANNEL_PAIR kTPM_Chnl_0

/* Interrupt to enable and flag to read; depends on the TPM channel pair used */
//#define TPM_CHANNEL_INTERRUPT_ENABLE kTPM_Chnl0Interrupt
#define TPM_CHANNEL_FLAG kTPM_Chnl0Flag

/* Interrupt number and interrupt handler for the TPM instance used */
//#define TPM_INTERRUPT_NUMBER TPM2_IRQn
#define TPM_LED_HANDLER TPM2_IRQHandler
/* Get source clock for TPM driver */
#define TPM_SOURCE_CLOCK CLOCK_GetFreq(kCLOCK_McgFllClk)

/*******************************************************************************
* Prototypes
******************************************************************************/

/*******************************************************************************
* Variables
******************************************************************************/
volatile bool brightnessUp = true; /* Indicate LED is brighter or dimmer */
volatile uint8_t updatedDutycycle = 10U;
volatile uint8_t getCharValue = 0U;

/*******************************************************************************
* Code
******************************************************************************/
/*!
* @brief Main function
*/
int main(void)
{
tpm_config_t tpmInfo;
tpm_chnl_pwm_signal_param_t tpmParam;
tpm_pwm_level_select_t pwmLevel = kTPM_LowTrue;
uint8_t deadtimeValue;
uint32_t filterVal;

/* Configure tpm params with frequency 24kHZ */
tpmParam.chnlNumber = BOARD_TPM_CHANNEL_PAIR;
tpmParam.level = pwmLevel;
tpmParam.dutyCyclePercent = 35U;
tpmParam.firstEdgeDelayPercent = 0U;

/* Board pin, clock, debug console init */
BOARD_InitPins();
BOARD_BootClockRUN();
BOARD_InitDebugConsole();

/* Select the clock source for the TPM counter as MCGPLLCLK */
CLOCK_SetTpmClock(1U);

/* Need a deadtime value of about 200nsec */
deadtimeValue = (((uint64_t)TPM_SOURCE_CLOCK * 400) / 1000000000) / 4;

/* Print a note to terminal */
PRINTF("\r\nTPM example to output combined complementary PWM signals on two channels\r\n");
PRINTF("\r\nIf an LED is connected to the TPM pin, you will see a change in LED brightness if you enter different values");
PRINTF("\r\nIf no LED is connected to the TPM pin, then probe the signal using an oscilloscope");

TPM_GetDefaultConfig(&tpmInfo);

/* Initialize TPM module */
TPM_Init(BOARD_TPM_BASEADDR, &tpmInfo);

TPM_SetupPwm(BOARD_TPM_BASEADDR, &tpmParam, 1U, kTPM_CombinedPwm, 24000U, TPM_SOURCE_CLOCK);

#if defined(FSL_FEATURE_TPM_HAS_POL) && FSL_FEATURE_TPM_HAS_POL
/* Change the polarity on the second channel of the pair to get complementary PWM signals */
BOARD_TPM_BASEADDR->POL |= (1U << ((BOARD_TPM_CHANNEL_PAIR * 2) + 1));
#endif

/* Set deadtime insertion for the channel pair using channel filter register */
filterVal = BOARD_TPM_BASEADDR->FILTER;
/* Clear the channel pair's filter values */
// filterVal &= ~((TPM_FILTER_CH0FVAL_MASK | TPM_FILTER_CH1FVAL_MASK)
// << (BOARD_TPM_CHANNEL_PAIR * (TPM_FILTER_CH0FVAL_SHIFT + TPM_FILTER_CH1FVAL_SHIFT)));
/* Shift the deadtime insertion value to the right place in the register */
filterVal |= (TPM_FILTER_CH0FVAL(deadtimeValue) | TPM_FILTER_CH1FVAL(deadtimeValue))
<< (BOARD_TPM_CHANNEL_PAIR * (TPM_FILTER_CH0FVAL_SHIFT + TPM_FILTER_CH1FVAL_SHIFT));
BOARD_TPM_BASEADDR->FILTER = filterVal;

TPM_StartTimer(BOARD_TPM_BASEADDR, kTPM_SystemClock);

while (1) {}

}

Is anybody who run it well?

Re: Complementary PWM with Deadtime insertion

gerardo_rodriguez — Fri, 27 Oct 2017 17:13:15 GMT

Helllo Vitaliy,

I have reported this issue to the SW team. I will update this thread when a resolution is available.

Regards,

Kinetis Microcontrollers中的主题 Complementary PWM with Deadtime insertion

Complementary PWM with Deadtime insertion

Re: Complementary PWM with Deadtime insertion