| //***************************************************************************** |
| // |
| // am_hal_pdm.c |
| //! @file |
| //! |
| //! @brief Functions for interfacing with Pulse Density Modulation (PDM). |
| //! |
| //! @addtogroup pdm2 DMEMS Microphon3 (PDM) |
| //! @ingroup apollo2hal |
| //! @{ |
| // |
| //***************************************************************************** |
| |
| //***************************************************************************** |
| // |
| // Copyright (c) 2017, 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. |
| // |
| // 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 v1.2.10-2-gea660ad-hotfix2 of the AmbiqSuite Development Package. |
| // |
| //***************************************************************************** |
| |
| #include <stdint.h> |
| #include <stdbool.h> |
| #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 |
| //! @} |
| // |
| //***************************************************************************** |
