/** * Copyright (c) 2015 - 2017, 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. * */ /** * @addtogroup nrf_pdm PDM HAL and driver * @ingroup nrf_drivers * @brief @tagAPI52 Pulse density modulation (PDM) interface APIs. * * The PDM HAL provides basic APIs for accessing the registers of the PDM interface peripheral. * The PDM driver provides APIs on a higher level. * * @defgroup nrf_drv_pdm PDM driver * @{ * @ingroup nrf_pdm * * @brief @tagAPI52 Pulse density modulation (PDM) interface driver. */ #ifndef NRF_DRV_PDM_H__ #define NRF_DRV_PDM_H__ #include "sdk_config.h" #include "nrf_pdm.h" #include "sdk_errors.h" #ifdef __cplusplus extern "C" { #endif #define NRF_PDM_MAX_BUFFER_SIZE 32768 /** * @brief PDM interface driver configuration structure. */ typedef struct { nrf_pdm_mode_t mode; ///< Interface operation mode. nrf_pdm_edge_t edge; ///< Sampling mode. uint8_t pin_clk; ///< CLK pin. uint8_t pin_din; ///< DIN pin. nrf_pdm_freq_t clock_freq; ///< Clock frequency. nrf_pdm_gain_t gain_l; ///< Left channel gain. nrf_pdm_gain_t gain_r; ///< Right channel gain. uint8_t interrupt_priority; ///< Interrupt priority. uint16_t buffer_length; ///< Length of a single buffer (in 16-bit words). int16_t * buffer_a; ///< Sample buffer A (filled first). int16_t * buffer_b; ///< Sample buffer B (filled after buffer A). } nrf_drv_pdm_config_t; /** * @brief Macro for setting @ref nrf_drv_pdm_config_t to default settings * in single ended mode. * * @param PIN_CLK CLK output pin. * @param PIN_DIN DIN input pin. * @param BUFF_A Sample buffer A (filled first). * @param BUFF_B Sample buffer B (filled after buffer A). * @param BUFF_LEN Length of a single buffer (in 16-bit words). */ #define NRF_DRV_PDM_DEFAULT_CONFIG(PIN_CLK, PIN_DIN, BUFF_A, BUFF_B, BUFF_LEN) \ { \ .mode = (nrf_pdm_mode_t)PDM_CONFIG_MODE, \ .edge = (nrf_pdm_edge_t)PDM_CONFIG_EDGE, \ .pin_clk = PIN_CLK, \ .pin_din = PIN_DIN, \ .clock_freq = (nrf_pdm_freq_t)PDM_CONFIG_CLOCK_FREQ, \ .gain_l = NRF_PDM_GAIN_DEFAULT, \ .gain_r = NRF_PDM_GAIN_DEFAULT, \ .interrupt_priority = PDM_CONFIG_IRQ_PRIORITY, \ .buffer_length = BUFF_LEN, \ .buffer_a = BUFF_A, \ .buffer_b = BUFF_B \ } /** * @brief Handler for PDM interface ready events. * * This event handler is called when a buffer is full and ready to be processed. * * @param[in] p_buffer Sample buffer pointer. * @param[in] length Buffer length in 16-bit words. */ typedef void (*nrf_drv_pdm_event_handler_t)(uint32_t * buffer, uint16_t length); /** * @brief Function for initializing the PDM interface. * * @param[in] p_config Pointer to a configuration structure. If NULL, the default one is used. * @param[in] event_handler Event handler provided by the user. * * @retval NRF_SUCCESS If initialization was successful. * @retval NRF_ERROR_INVALID_STATE If the driver is already initialized. * @retval NRF_ERROR_INVALID_PARAM If invalid parameters were specified. */ ret_code_t nrf_drv_pdm_init(nrf_drv_pdm_config_t const * p_config, nrf_drv_pdm_event_handler_t event_handler); /** * @brief Function for uninitializing the PDM interface. * * This function stops PDM sampling, if it is in progress. */ void nrf_drv_pdm_uninit(void); /** * @brief Function for getting the address of a PDM interface task. * * @param[in] task Task. * * @return Task address. */ __STATIC_INLINE uint32_t nrf_drv_pdm_task_address_get(nrf_pdm_task_t task) { return nrf_pdm_task_address_get(task); } /** * @brief Function for getting the state of the PDM interface. * * @retval TRUE If the PDM interface is enabled. * @retval FALSE If the PDM interface is disabled. */ __STATIC_INLINE bool nrf_drv_pdm_enable_check() { return nrf_pdm_enable_check(); } /** * @brief Function for starting PDM sampling. * * @retval NRF_SUCCESS If sampling was started successfully or was already in progress. * @retval NRF_ERROR_BUSY If a previous start/stop operation is in progress. */ ret_code_t nrf_drv_pdm_start(void); /** * @brief Function for stopping PDM sampling. * * When this function is called, the PDM interface is stopped after finishing * the current frame. * The event handler function might be called once more after calling this function. * * @retval NRF_SUCCESS If sampling was stopped successfully or was already stopped before. * @retval NRF_ERROR_BUSY If a previous start/stop operation is in progress. */ ret_code_t nrf_drv_pdm_stop(void); #ifdef __cplusplus } #endif #endif // NRF_DRV_PDM_H__ /** @} */