Files

stm8s_beep.c
/** ****************************************************************************** * @file stm8s_beep.c * @author MCD Application Team * @version V2.2.0 * @date 30-September-2014 * @brief This file contains all the functions for the BEEP peripheral. ****************************************************************************** * @attention * * <h2><center>&copy; COPYRIGHT 2014 STMicroelectronics</center></h2> * * Licensed under MCD-ST Liberty SW License Agreement V2, (the "License"); * You may not use this file except in compliance with the License. * You may obtain a copy of the License at: * * http://www.st.com/software_license_agreement_liberty_v2 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. * ****************************************************************************** */ /* Includes ------------------------------------------------------------------*/ #include "stm8s_beep.h" /** @addtogroup STM8S_StdPeriph_Driver * @{ */ /* Private typedef -----------------------------------------------------------*/ /* Private define ------------------------------------------------------------*/ /* Private macro -------------------------------------------------------------*/ /* Private variables ---------------------------------------------------------*/ /* Private function prototypes -----------------------------------------------*/ /* Private functions ---------------------------------------------------------*/ /* Public functions ----------------------------------------------------------*/ /** * @addtogroup BEEP_Public_Functions * @{ */ /** * @brief Deinitializes the BEEP peripheral registers to their default reset * values. * @param None * @retval None */ void BEEP_DeInit(void) { BEEP->CSR = BEEP_CSR_RESET_VALUE; } /** * @brief Initializes the BEEP function according to the specified parameters. * @param BEEP_Frequency Frequency selection. * can be one of the values of @ref BEEP_Frequency_TypeDef. * @retval None * @par Required preconditions: * The LS RC calibration must be performed before calling this function. */ void BEEP_Init(BEEP_Frequency_TypeDef BEEP_Frequency) { /* Check parameter */ assert_param(IS_BEEP_FREQUENCY_OK(BEEP_Frequency)); /* Set a default calibration value if no calibration is done */ if ((BEEP->CSR & BEEP_CSR_BEEPDIV) == BEEP_CSR_BEEPDIV) { BEEP->CSR &= (uint8_t)(~BEEP_CSR_BEEPDIV); /* Clear bits */ BEEP->CSR |= BEEP_CALIBRATION_DEFAULT; } /* Select the output frequency */ BEEP->CSR &= (uint8_t)(~BEEP_CSR_BEEPSEL); BEEP->CSR |= (uint8_t)(BEEP_Frequency); } /** * @brief Enable or disable the BEEP function. * @param NewState Indicates the new state of the BEEP function. * @retval None * @par Required preconditions: * Initialisation of BEEP and LS RC calibration must be done before. */ void BEEP_Cmd(FunctionalState NewState) { if (NewState != DISABLE) { /* Enable the BEEP peripheral */ BEEP->CSR |= BEEP_CSR_BEEPEN; } else { /* Disable the BEEP peripheral */ BEEP->CSR &= (uint8_t)(~BEEP_CSR_BEEPEN); } } /** * @brief Update CSR register with the measured LSI frequency. * @par Note on the APR calculation: * A is the integer part of LSIFreqkHz/4 and x the decimal part. * x <= A/(1+2A) is equivalent to A >= x(1+2A) and also to 4A >= 4x(1+2A) [F1] * but we know that A + x = LSIFreqkHz/4 ==> 4x = LSIFreqkHz-4A * so [F1] can be written : * 4A >= (LSIFreqkHz-4A)(1+2A) * @param LSIFreqHz Low Speed RC frequency measured by timer (in Hz). * @retval None * @par Required preconditions: * - BEEP must be disabled to avoid unwanted interrupts. */ void BEEP_LSICalibrationConfig(uint32_t LSIFreqHz) { uint16_t lsifreqkhz; uint16_t A; /* Check parameter */ assert_param(IS_LSI_FREQUENCY_OK(LSIFreqHz)); lsifreqkhz = (uint16_t)(LSIFreqHz / 1000); /* Converts value in kHz */ /* Calculation of BEEPER calibration value */ BEEP->CSR &= (uint8_t)(~BEEP_CSR_BEEPDIV); /* Clear bits */ A = (uint16_t)(lsifreqkhz >> 3U); /* Division by 8, keep integer part only */ if ((8U * A) >= ((lsifreqkhz - (8U * A)) * (1U + (2U * A)))) { BEEP->CSR |= (uint8_t)(A - 2U); } else { BEEP->CSR |= (uint8_t)(A - 1U); } } /** * @} */ /** * @} */ /************************ (C) COPYRIGHT STMicroelectronics *****END OF FILE****/
Report a bug