//***************************************************************************** // // am_hal_pdm.c //! @file //! //! @brief Functions for interfacing with Pulse Density Modulation (PDM). //! //! @addtogroup pdm2 DMEMS Microphon3 (PDM) //! @ingroup apollo2hal //! @{ // //***************************************************************************** //***************************************************************************** // // Copyright (c) 2020, Ambiq Micro // 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 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 the copyright holder nor the names of its // contributors may be used to endorse or promote products derived from this // software without specific prior written permission. // // Third party software included in this distribution is subject to the // additional license terms as defined in the /docs/licenses directory. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER 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. // // This is part of revision 2.4.2 of the AmbiqSuite Development Package. // //***************************************************************************** #include #include #include "am_mcu_apollo.h" //***************************************************************************** // //! @brief Configure the PDM module. //! //! This function reads the an \e am_hal_pdm_config_t structure and uses it to //! set up the PDM module. //! //! Please see the information on the am_hal_pdm_config_t configuration //! structure, found in am_hal_pdm.h, for more information on the parameters //! that may be set by this function. //! //! @return None. // //***************************************************************************** void am_hal_pdm_config(am_hal_pdm_config_t *psConfig) { // // setup the PDM PCFG register // AM_REG(PDM, PCFG) = psConfig->ui32PDMConfigReg; // // setup the PDM VCFG register // AM_REG(PDM, VCFG) = psConfig->ui32VoiceConfigReg; // // setup the PDM FIFO Threshold register // AM_REG(PDM, FTHR) = psConfig->ui32FIFOThreshold; // // Flush the FIFO for good measure. // am_hal_pdm_fifo_flush(); } //***************************************************************************** // //! @brief Enable the PDM module. //! //! This function enables the PDM module in the mode previously defined by //! am_hal_pdm_config(). //! //! @return None. // //***************************************************************************** void am_hal_pdm_enable(void) { AM_REG(PDM, PCFG) |= AM_REG_PDM_PCFG_PDMCORE_EN; AM_REG(PDM, VCFG) |= ( AM_REG_PDM_VCFG_IOCLKEN_EN | AM_REG_PDM_VCFG_PDMCLK_EN | AM_REG_PDM_VCFG_RSTB_NORM ); } //***************************************************************************** // //! @brief Disable the PDM module. //! //! This function disables the PDM module. //! //! @return None. // //***************************************************************************** void am_hal_pdm_disable(void) { AM_REG(PDM, PCFG) &= ~ AM_REG_PDM_PCFG_PDMCORE_EN; AM_REG(PDM, VCFG) &= ~ ( AM_REG_PDM_VCFG_IOCLKEN_EN | AM_REG_PDM_VCFG_PDMCLK_EN | AM_REG_PDM_VCFG_RSTB_NORM ); } //***************************************************************************** // //! @brief Return the PDM Interrupt status. //! //! @param bEnabledOnly - return only the enabled interrupts. //! //! Use this function to get the PDM interrupt status. //! //! @return intrrupt status // //***************************************************************************** uint32_t am_hal_pdm_int_status_get(bool bEnabledOnly) { if ( bEnabledOnly ) { uint32_t u32RetVal = AM_REG(PDM, INTSTAT); return u32RetVal & AM_REG(PDM, INTEN); } else { return AM_REG(PDM, INTSTAT); } } //***************************************************************************** // // End the doxygen group //! @} // //*****************************************************************************