Hi,
I am trying to interfacing the IMP34DT05 Microphone with the NRF52840. I can see in the DSO that CLK pulse is generating in the NRF52840, but there no data pulse from the Microphone. I am new to PDM interface, so help me out of this problem.....What will be the issues?
SDK17.0
/**
* Copyright (c) 2015 - 2020, Nordic Semiconductor ASA
*
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification,
* are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this
* list of conditions and the following disclaimer.
*
* 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
* conditions and the following disclaimer in the documentation and/or other
* 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.
*
* 4. This software, with or without modification, must only be used with a
* Nordic Semiconductor ASA integrated circuit.
*
* 5. Any software provided in binary form under this license must not be reverse
* engineered, decompiled, modified and/or disassembled.
*
* THIS SOFTWARE IS PROVIDED BY NORDIC SEMICONDUCTOR ASA "AS IS" AND ANY EXPRESS
* OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY, NONINFRINGEMENT, AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL NORDIC SEMICONDUCTOR ASA OR CONTRIBUTORS BE
* LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
* GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
*/
/**
* @brief Blinky Sample Application main file.
*
* This file contains the source code for a sample server application using the LED Button service.
*/
#include <stdint.h>
#include <string.h>
#include "nordic_common.h"
#include "nrf.h"
#include "app_error.h"
#include "ble.h"
#include "ble_err.h"
#include "ble_hci.h"
#include "ble_srv_common.h"
#include "ble_advdata.h"
#include "ble_conn_params.h"
#include "nrf_sdh.h"
#include "nrf_sdh_ble.h"
#include "boards.h"
#include "app_timer.h"
#include "app_button.h"
#include "ble_lbs.h"
#include "nrf_ble_gatt.h"
#include "nrf_ble_qwr.h"
#include "nrf_pwr_mgmt.h"
#include "nrf_log.h"
#include "nrf_log_ctrl.h"
#include "nrf_log_default_backends.h"
#include "nrf_drv_pdm.h"
#define ADVERTISING_LED BSP_BOARD_LED_0 /**< Is on when device is advertising. */
#define CONNECTED_LED BSP_BOARD_LED_1 /**< Is on when device has connected. */
#define LEDBUTTON_LED BSP_BOARD_LED_2 /**< LED to be toggled with the help of the LED Button Service. */
#define LEDBUTTON_BUTTON BSP_BUTTON_0 /**< Button that will trigger the notification event with the LED Button Service */
#define DEVICE_NAME "Nordic_Blinky" /**< Name of device. Will be included in the advertising data. */
#define APP_BLE_OBSERVER_PRIO 3 /**< Application's BLE observer priority. You shouldn't need to modify this value. */
#define APP_BLE_CONN_CFG_TAG 1 /**< A tag identifying the SoftDevice BLE configuration. */
#define APP_ADV_INTERVAL 64 /**< The advertising interval (in units of 0.625 ms; this value corresponds to 40 ms). */
#define APP_ADV_DURATION BLE_GAP_ADV_TIMEOUT_GENERAL_UNLIMITED /**< The advertising time-out (in units of seconds). When set to 0, we will never time out. */
#define MIN_CONN_INTERVAL MSEC_TO_UNITS(100, UNIT_1_25_MS) /**< Minimum acceptable connection interval (0.5 seconds). */
#define MAX_CONN_INTERVAL MSEC_TO_UNITS(200, UNIT_1_25_MS) /**< Maximum acceptable connection interval (1 second). */
#define SLAVE_LATENCY 0 /**< Slave latency. */
#define CONN_SUP_TIMEOUT MSEC_TO_UNITS(4000, UNIT_10_MS) /**< Connection supervisory time-out (4 seconds). */
#define FIRST_CONN_PARAMS_UPDATE_DELAY APP_TIMER_TICKS(20000) /**< Time from initiating event (connect or start of notification) to first time sd_ble_gap_conn_param_update is called (15 seconds). */
#define NEXT_CONN_PARAMS_UPDATE_DELAY APP_TIMER_TICKS(5000) /**< Time between each call to sd_ble_gap_conn_param_update after the first call (5 seconds). */
#define MAX_CONN_PARAMS_UPDATE_COUNT 3 /**< Number of attempts before giving up the connection parameter negotiation. */
#define BUTTON_DETECTION_DELAY APP_TIMER_TICKS(50) /**< Delay from a GPIOTE event until a button is reported as pushed (in number of timer ticks). */
#define DEAD_BEEF 0xDEADBEEF /**< Value used as error code on stack dump, can be used to identify stack location on stack unwind. */
BLE_LBS_DEF(m_lbs); /**< LED Button Service instance. */
NRF_BLE_GATT_DEF(m_gatt); /**< GATT module instance. */
NRF_BLE_QWR_DEF(m_qwr); /**< Context for the Queued Write module.*/
static uint16_t m_conn_handle = BLE_CONN_HANDLE_INVALID; /**< Handle of the current connection. */
static uint8_t m_adv_handle = BLE_GAP_ADV_SET_HANDLE_NOT_SET; /**< Advertising handle used to identify an advertising set. */
static uint8_t m_enc_advdata[BLE_GAP_ADV_SET_DATA_SIZE_MAX]; /**< Buffer for storing an encoded advertising set. */
static uint8_t m_enc_scan_response_data[BLE_GAP_ADV_SET_DATA_SIZE_MAX]; /**< Buffer for storing an encoded scan data. */
#define CONFIG_PDM_BUFFER_SIZE_SAMPLES 320
// <o> PDM Decimation Filter Gain <0x00-0x50>
// <i> For details on the PDM decimation filter, see the 'Decimation filter' section in the nRF52 Product Specification document.
#define CONFIG_PDM_GAIN 0x28
// <o> PDM CLK Pin
#define CONFIG_IO_PDM_CLK 0x06
// <o> PDM DATA Pin
#define CONFIG_IO_PDM_DATA 0x05
// <o> PDM Microphone Power Control Pin
#define CONFIG_IO_PDM_MIC_PWR_CTRL 0x07
/**@brief Audio buffer handler. */
typedef void (*drv_audio_buffer_handler_t)(int16_t *p_buffer, uint16_t samples);
static int16_t m_pdm_buff[2][CONFIG_PDM_BUFFER_SIZE_SAMPLES];
static drv_audio_buffer_handler_t m_buffer_handler;
static void m_audio_buffer_handler(int16_t *p_buffer, uint16_t samples)
{
// Audio processing
}
static void drv_audio_pdm_event_handler(uint32_t *p_buffer, uint16_t length)
{
m_buffer_handler((int16_t *)p_buffer, length);
}
uint32_t drv_audio_init(drv_audio_buffer_handler_t buffer_handler)
{
//nrf_drv_pdm_config_t pdm_cfg = NRF_DRV_PDM_DEFAULT_CONFIG(CONFIG_IO_PDM_CLK,
// CONFIG_IO_PDM_DATA,
// m_pdm_buff[0],
// m_pdm_buff[1],
// CONFIG_PDM_BUFFER_SIZE_SAMPLES);
nrf_drv_pdm_config_t pdm_cfg = NRF_DRV_PDM_DEFAULT_CONFIG(CONFIG_IO_PDM_CLK,CONFIG_IO_PDM_DATA);
if (buffer_handler == NULL)
{
return NRF_ERROR_INVALID_PARAM;
}
m_buffer_handler = buffer_handler;
pdm_cfg.gain_l = CONFIG_PDM_GAIN;
pdm_cfg.gain_r = CONFIG_PDM_GAIN;
pdm_cfg.clock_freq = PDM_PDMCLKCTRL_FREQ_1333K;
return nrf_drv_pdm_init(&pdm_cfg, drv_audio_pdm_event_handler);
}
/**@brief Struct that contains pointers to the encoded advertising data. */
static ble_gap_adv_data_t m_adv_data =
{
.adv_data =
{
.p_data = m_enc_advdata,
.len = BLE_GAP_ADV_SET_DATA_SIZE_MAX
},
.scan_rsp_data =
{
.p_data = m_enc_scan_response_data,
.len = BLE_GAP_ADV_SET_DATA_SIZE_MAX
}
};
/**@brief Function for assert macro callback.
*
* @details This function will be called in case of an assert in the SoftDevice.
*
* @warning This handler is an example only and does not fit a final product. You need to analyze
* how your product is supposed to react in case of Assert.
* @warning On assert from the SoftDevice, the system can only recover on reset.
*
* @param[in] line_num Line number of the failing ASSERT call.
* @param[in] p_file_name File name of the failing ASSERT call.
*/
void assert_nrf_callback(uint16_t line_num, const uint8_t * p_file_name)
{
app_error_handler(DEAD_BEEF, line_num, p_file_name);
}
/**@brief Function for the LEDs initialization.
*
* @details Initializes all LEDs used by the application.
*/
static void leds_init(void)
{
bsp_board_init(BSP_INIT_LEDS);
}
/**@brief Function for the Timer initialization.
*
* @details Initializes the timer module.
*/
static void timers_init(void)
{
// Initialize timer module, making it use the scheduler
ret_code_t err_code = app_timer_init();
APP_ERROR_CHECK(err_code);
}
/**@brief Function for the GAP initialization.
*
* @details This function sets up all the necessary GAP (Generic Access Profile) parameters of the
* device including the device name, appearance, and the preferred connection parameters.
*/
static void gap_params_init(void)
{
ret_code_t err_code;
ble_gap_conn_params_t gap_conn_params;
ble_gap_conn_sec_mode_t sec_mode;
BLE_GAP_CONN_SEC_MODE_SET_OPEN(&sec_mode);
err_code = sd_ble_gap_device_name_set(&sec_mode,
(const uint8_t *)DEVICE_NAME,
strlen(DEVICE_NAME));
APP_ERROR_CHECK(err_code);
memset(&gap_conn_params, 0, sizeof(gap_conn_params));
gap_conn_params.min_conn_interval = MIN_CONN_INTERVAL;
gap_conn_params.max_conn_interval = MAX_CONN_INTERVAL;
gap_conn_params.slave_latency = SLAVE_LATENCY;
gap_conn_params.conn_sup_timeout = CONN_SUP_TIMEOUT;
err_code = sd_ble_gap_ppcp_set(&gap_conn_params);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for initializing the GATT module.
*/
static void gatt_init(void)
{
ret_code_t err_code = nrf_ble_gatt_init(&m_gatt, NULL);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for initializing the Advertising functionality.
*
* @details Encodes the required advertising data and passes it to the stack.
* Also builds a structure to be passed to the stack when starting advertising.
*/
static void advertising_init(void)
{
ret_code_t err_code;
ble_advdata_t advdata;
ble_advdata_t srdata;
ble_uuid_t adv_uuids[] = {{LBS_UUID_SERVICE, m_lbs.uuid_type}};
// Build and set advertising data.
memset(&advdata, 0, sizeof(advdata));
advdata.name_type = BLE_ADVDATA_FULL_NAME;
advdata.include_appearance = true;
advdata.flags = BLE_GAP_ADV_FLAGS_LE_ONLY_GENERAL_DISC_MODE;
memset(&srdata, 0, sizeof(srdata));
srdata.uuids_complete.uuid_cnt = sizeof(adv_uuids) / sizeof(adv_uuids[0]);
srdata.uuids_complete.p_uuids = adv_uuids;
err_code = ble_advdata_encode(&advdata, m_adv_data.adv_data.p_data, &m_adv_data.adv_data.len);
APP_ERROR_CHECK(err_code);
err_code = ble_advdata_encode(&srdata, m_adv_data.scan_rsp_data.p_data, &m_adv_data.scan_rsp_data.len);
APP_ERROR_CHECK(err_code);
ble_gap_adv_params_t adv_params;
// Set advertising parameters.
memset(&adv_params, 0, sizeof(adv_params));
adv_params.primary_phy = BLE_GAP_PHY_1MBPS;
adv_params.duration = APP_ADV_DURATION;
adv_params.properties.type = BLE_GAP_ADV_TYPE_CONNECTABLE_SCANNABLE_UNDIRECTED;
adv_params.p_peer_addr = NULL;
adv_params.filter_policy = BLE_GAP_ADV_FP_ANY;
adv_params.interval = APP_ADV_INTERVAL;
err_code = sd_ble_gap_adv_set_configure(&m_adv_handle, &m_adv_data, &adv_params);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for handling Queued Write Module errors.
*
* @details A pointer to this function will be passed to each service which may need to inform the
* application about an error.
*
* @param[in] nrf_error Error code containing information about what went wrong.
*/
static void nrf_qwr_error_handler(uint32_t nrf_error)
{
APP_ERROR_HANDLER(nrf_error);
}
/**@brief Function for handling write events to the LED characteristic.
*
* @param[in] p_lbs Instance of LED Button Service to which the write applies.
* @param[in] led_state Written/desired state of the LED.
*/
static void led_write_handler(uint16_t conn_handle, ble_lbs_t * p_lbs, uint8_t led_state)
{
if (led_state)
{
bsp_board_led_on(LEDBUTTON_LED);
NRF_LOG_INFO("Received LED ON!");
}
else
{
bsp_board_led_off(LEDBUTTON_LED);
NRF_LOG_INFO("Received LED OFF!");
}
}
/**@brief Function for initializing services that will be used by the application.
*/
static void services_init(void)
{
ret_code_t err_code;
ble_lbs_init_t init = {0};
nrf_ble_qwr_init_t qwr_init = {0};
// Initialize Queued Write Module.
qwr_init.error_handler = nrf_qwr_error_handler;
err_code = nrf_ble_qwr_init(&m_qwr, &qwr_init);
APP_ERROR_CHECK(err_code);
// Initialize LBS.
init.led_write_handler = led_write_handler;
err_code = ble_lbs_init(&m_lbs, &init);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for handling the Connection Parameters Module.
*
* @details This function will be called for all events in the Connection Parameters Module that
* are passed to the application.
*
* @note All this function does is to disconnect. This could have been done by simply
* setting the disconnect_on_fail config parameter, but instead we use the event
* handler mechanism to demonstrate its use.
*
* @param[in] p_evt Event received from the Connection Parameters Module.
*/
static void on_conn_params_evt(ble_conn_params_evt_t * p_evt)
{
ret_code_t err_code;
if (p_evt->evt_type == BLE_CONN_PARAMS_EVT_FAILED)
{
err_code = sd_ble_gap_disconnect(m_conn_handle, BLE_HCI_CONN_INTERVAL_UNACCEPTABLE);
APP_ERROR_CHECK(err_code);
}
}
/**@brief Function for handling a Connection Parameters error.
*
* @param[in] nrf_error Error code containing information about what went wrong.
*/
static void conn_params_error_handler(uint32_t nrf_error)
{
APP_ERROR_HANDLER(nrf_error);
}
/**@brief Function for initializing the Connection Parameters module.
*/
static void conn_params_init(void)
{
ret_code_t err_code;
ble_conn_params_init_t cp_init;
memset(&cp_init, 0, sizeof(cp_init));
cp_init.p_conn_params = NULL;
cp_init.first_conn_params_update_delay = FIRST_CONN_PARAMS_UPDATE_DELAY;
cp_init.next_conn_params_update_delay = NEXT_CONN_PARAMS_UPDATE_DELAY;
cp_init.max_conn_params_update_count = MAX_CONN_PARAMS_UPDATE_COUNT;
cp_init.start_on_notify_cccd_handle = BLE_GATT_HANDLE_INVALID;
cp_init.disconnect_on_fail = false;
cp_init.evt_handler = on_conn_params_evt;
cp_init.error_handler = conn_params_error_handler;
err_code = ble_conn_params_init(&cp_init);
APP_ERROR_CHECK(err_code);
}
/**@brief Function for starting advertising.
*/
static void advertising_start(void)
{
ret_code_t err_code;
err_code = sd_ble_gap_adv_start(m_adv_handle, APP_BLE_CONN_CFG_TAG);
APP_ERROR_CHECK(err_code);
bsp_board_led_on(ADVERTISING_LED);
}
/**@brief Function for handling BLE events.
*
* @param[in] p_ble_evt Bluetooth stack event.
* @param[in] p_context Unused.
*/
static void ble_evt_handler(ble_evt_t const * p_ble_evt, void * p_context)
{
ret_code_t err_code;
switch (p_ble_evt->header.evt_id)
{
case BLE_GAP_EVT_CONNECTED:
NRF_LOG_INFO("Connected");
bsp_board_led_on(CONNECTED_LED);
bsp_board_led_off(ADVERTISING_LED);
m_conn_handle = p_ble_evt->evt.gap_evt.conn_handle;
err_code = nrf_ble_qwr_conn_handle_assign(&m_qwr, m_conn_handle);
APP_ERROR_CHECK(err_code);
err_code = app_button_enable();
APP_ERROR_CHECK(err_code);
break;
case BLE_GAP_EVT_DISCONNECTED:
NRF_LOG_INFO("Disconnected");
bsp_board_led_off(CONNECTED_LED);
m_conn_handle = BLE_CONN_HANDLE_INVALID;
err_code = app_button_disable();
APP_ERROR_CHECK(err_code);
advertising_start();
break;
case BLE_GAP_EVT_SEC_PARAMS_REQUEST:
// Pairing not supported
err_code = sd_ble_gap_sec_params_reply(m_conn_handle,
BLE_GAP_SEC_STATUS_PAIRING_NOT_SUPP,
NULL,
NULL);
APP_ERROR_CHECK(err_code);
break;
case BLE_GAP_EVT_PHY_UPDATE_REQUEST:
{
NRF_LOG_DEBUG("PHY update request.");
ble_gap_phys_t const phys =
{
.rx_phys = BLE_GAP_PHY_AUTO,
.tx_phys = BLE_GAP_PHY_AUTO,
};
err_code = sd_ble_gap_phy_update(p_ble_evt->evt.gap_evt.conn_handle, &phys);
APP_ERROR_CHECK(err_code);
} break;
case BLE_GATTS_EVT_SYS_ATTR_MISSING:
// No system attributes have been stored.
err_code = sd_ble_gatts_sys_attr_set(m_conn_handle, NULL, 0, 0);
APP_ERROR_CHECK(err_code);
break;
case BLE_GATTC_EVT_TIMEOUT:
// Disconnect on GATT Client timeout event.
NRF_LOG_DEBUG("GATT Client Timeout.");
err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gattc_evt.conn_handle,
BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
APP_ERROR_CHECK(err_code);
break;
case BLE_GATTS_EVT_TIMEOUT:
// Disconnect on GATT Server timeout event.
NRF_LOG_DEBUG("GATT Server Timeout.");
err_code = sd_ble_gap_disconnect(p_ble_evt->evt.gatts_evt.conn_handle,
BLE_HCI_REMOTE_USER_TERMINATED_CONNECTION);
APP_ERROR_CHECK(err_code);
break;
default:
// No implementation needed.
break;
}
}
/**@brief Function for initializing the BLE stack.
*
* @details Initializes the SoftDevice and the BLE event interrupt.
*/
static void ble_stack_init(void)
{
ret_code_t err_code;
err_code = nrf_sdh_enable_request();
APP_ERROR_CHECK(err_code);
// Configure the BLE stack using the default settings.
// Fetch the start address of the application RAM.
uint32_t ram_start = 0;
err_code = nrf_sdh_ble_default_cfg_set(APP_BLE_CONN_CFG_TAG, &ram_start);
APP_ERROR_CHECK(err_code);
// Enable BLE stack.
err_code = nrf_sdh_ble_enable(&ram_start);
APP_ERROR_CHECK(err_code);
// Register a handler for BLE events.
NRF_SDH_BLE_OBSERVER(m_ble_observer, APP_BLE_OBSERVER_PRIO, ble_evt_handler, NULL);
}
/**@brief Function for handling events from the button handler module.
*
* @param[in] pin_no The pin that the event applies to.
* @param[in] button_action The button action (press/release).
*/
static void button_event_handler(uint8_t pin_no, uint8_t button_action)
{
ret_code_t err_code;
switch (pin_no)
{
case LEDBUTTON_BUTTON:
NRF_LOG_INFO("Send button state change.");
err_code = ble_lbs_on_button_change(m_conn_handle, &m_lbs, button_action);
if (err_code != NRF_SUCCESS &&
err_code != BLE_ERROR_INVALID_CONN_HANDLE &&
err_code != NRF_ERROR_INVALID_STATE &&
err_code != BLE_ERROR_GATTS_SYS_ATTR_MISSING)
{
APP_ERROR_CHECK(err_code);
}
break;
default:
APP_ERROR_HANDLER(pin_no);
break;
}
}
/**@brief Function for initializing the button handler module.
*/
static void buttons_init(void)
{
ret_code_t err_code;
//The array must be static because a pointer to it will be saved in the button handler module.
static app_button_cfg_t buttons[] =
{
{LEDBUTTON_BUTTON, false, BUTTON_PULL, button_event_handler}
};
err_code = app_button_init(buttons, ARRAY_SIZE(buttons),
BUTTON_DETECTION_DELAY);
APP_ERROR_CHECK(err_code);
}
static void log_init(void)
{
ret_code_t err_code = NRF_LOG_INIT(NULL);
APP_ERROR_CHECK(err_code);
NRF_LOG_DEFAULT_BACKENDS_INIT();
}
/**@brief Function for initializing power management.
*/
static void power_management_init(void)
{
ret_code_t err_code;
err_code = nrf_pwr_mgmt_init();
APP_ERROR_CHECK(err_code);
}
/**@brief Function for handling the idle state (main loop).
*
* @details If there is no pending log operation, then sleep until next the next event occurs.
*/
static void idle_state_handle(void)
{
if (NRF_LOG_PROCESS() == false)
{
nrf_pwr_mgmt_run();
}
}
/**@brief Function for application main entry.
*/
int main(void)
{
// Initialize.
log_init();
leds_init();
timers_init();
buttons_init();
power_management_init();
ble_stack_init();
gap_params_init();
gatt_init();
services_init();
advertising_init();
conn_params_init();
// Start execution.
NRF_LOG_INFO("Blinky example started.");
advertising_start();
uint32_t err_code;
err_code = drv_audio_init(m_audio_buffer_handler);
APP_ERROR_CHECK(err_code);
err_code = nrf_drv_pdm_start();
APP_ERROR_CHECK(err_code);
//err_code = nrfx_pdm_start();
// APP_ERROR_CHECK(err_code);
// Enter main loop.
for (;;)
{
idle_state_handle();
}
}
/**
* @}
*/
Regards,
Nishanth M
