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Audio with PWM

hi, I am using nrf52832 development board for PWM and I want to play an audio (.wav) file using PWM, I am unable to play the audio clip using the PWM, and same audio file I am able to play in Arduino UNO board. Can you please tell me the procedure to play the audio clip in the nrf52832 board using PWM. I am using The SDK version 15.3.0, I have taken reference of pwm driver example to develop. nRF5_SDK_15.3.0/examples/peripheral/pwm_driver.

please find below the attachments of code and audio file .

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 * 1. Redistributions of source code must retain the above copyright notice, this
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 * 2. Redistributions in binary form, except as embedded into a Nordic
 *    Semiconductor ASA integrated circuit in a product or a software update for
 *    such product, must reproduce the above copyright notice, this list of
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 *    materials provided with the distribution.
 *
 * 3. Neither the name of Nordic Semiconductor ASA nor the names of its
 *    contributors may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
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 * 4. This software, with or without modification, must only be used with a
 *    Nordic Semiconductor ASA integrated circuit.
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/** @file
 * @defgroup pwm_example_main main.c
 * @{
 * @ingroup pwm_example
 *
 * @brief PWM Example Application main file.
 *
 * This file contains the source code for a sample application using PWM.
 */

#include <stdio.h>
#include <string.h>
#include "nrf_drv_pwm.h"
#include "app_util_platform.h"
#include "app_error.h"
#include "boards.h"
#include "bsp.h"
#include "app_timer.h"
#include "nrf_drv_clock.h"
#include "nrf_delay.h"
#include "tone.h"
#include "airtel.h"
#include "nrf_gpio.h"

#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"

#define AUDIO 2
static nrf_drv_pwm_t m_pwm0 = NRF_DRV_PWM_INSTANCE(0);


static void pwm_stop(void)
{
	nrf_drv_pwm_uninit(&m_pwm0);
	nrf_gpio_pin_clear(AUDIO);
}

nrf_pwm_values_individual_t seq_values;
nrf_pwm_sequence_t const seq =
{
		.values.p_individual = &seq_values,
		.length          = NRF_PWM_VALUES_LENGTH(seq_values),
		.repeats         = 0,
		.end_delay       = 0
};


void play_audio(void)
{
	uint16_t len = sizeof(airtel)/sizeof(airtel[1]);
	for(uint16_t i = 0;i<len;i++)
	{
		seq_values.channel_0 = airtel[i];
		nrf_delay_ms(1);
		(void)nrf_drv_pwm_simple_playback(&m_pwm0, &seq, 1, NRF_DRV_PWM_FLAG_STOP);
	}
}



static void vib_pwm_init(void)
{
	nrf_drv_pwm_config_t const config0 =
	{
			.output_pins =
			{
					AUDIO ,   						      // channel 0
					NRF_DRV_PWM_PIN_NOT_USED,             // channel 1
					NRF_DRV_PWM_PIN_NOT_USED,             // channel 2
					NRF_DRV_PWM_PIN_NOT_USED,             // channel 3
			},
			.irq_priority = APP_IRQ_PRIORITY_LOWEST,
			.base_clock   = NRF_PWM_CLK_125kHz,
			.count_mode   = NRF_PWM_MODE_UP,
			.top_value    = 255,
			.load_mode    = NRF_PWM_LOAD_COMMON,
			.step_mode    = NRF_PWM_STEP_AUTO
	};
	APP_ERROR_CHECK(nrf_drv_pwm_init(&m_pwm0, &config0, NULL));
}

/*
 * Applicatin entry
 */
int main(void)
{
	nrf_gpio_pin_dir_set(AUDIO,NRF_GPIO_PIN_DIR_OUTPUT);
	nrf_gpio_pin_clear(AUDIO);
	for (;;)
	{
		vib_pwm_init();
		play_audio();
		pwm_stop();
		nrf_delay_ms(2000);
		printf("audio\r\n");
	}
}

airtel.h

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