stm8s_spi.c

STM8s

/**
  ******************************************************************************
  * @file stm8s_spi.c
  * @brief This file contains all the functions for the SPI peripheral.
  * @author STMicroelectronics - MCD Application Team
  * @version V1.1.1
  * @date 06/05/2009
  ******************************************************************************
  *
  * THE PRESENT FIRMWARE WHICH IS FOR GUIDANCE ONLY AIMS AT PROVIDING CUSTOMERS
  * WITH CODING INFORMATION REGARDING THEIR PRODUCTS IN ORDER FOR THEM TO SAVE
  * TIME. AS A RESULT, STMICROELECTRONICS SHALL NOT BE HELD LIABLE FOR ANY
  * DIRECT, INDIRECT OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
  * FROM THE CONTENT OF SUCH FIRMWARE AND/OR THE USE MADE BY CUSTOMERS OF THE
  * CODING INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.
  *
  * <h2><center>&copy; COPYRIGHT 2009 STMicroelectronics</center></h2>
  * @image html logo.bmp
  ******************************************************************************
  */

/* Includes ------------------------------------------------------------------*/
#include "stm8s_spi.h"

/* Private define ------------------------------------------------------------*/
/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/
/* Public functions ----------------------------------------------------------*/

/** @addtogroup SPI_Public_Functions
  * @{
  */

/**
  * @brief Deinitializes the SPI peripheral registers to their default reset values.
  * @par Parameters:
  * None
  * @retval
  * None
  */
void SPI_DeInit(void)
{
    SPI->CR1    = SPI_CR1_RESET_VALUE;
    SPI->CR2    = SPI_CR2_RESET_VALUE;
    SPI->ICR    = SPI_ICR_RESET_VALUE;
    SPI->SR     = SPI_SR_RESET_VALUE;
    SPI->CRCPR  = SPI_CRCPR_RESET_VALUE;
}

/**
  * @brief Initializes the SPI according to the specified parameters.
  * @param[in] FirstBit : This parameter can be any of the @ref SPI_FirstBit_TypeDef enumeration.
  * @param[in] BaudRatePrescaler : This parameter can be any of the @ref SPI_BaudRatePrescaler_TypeDef enumeration.
  * @param[in] Mode : This parameter can be any of the  @ref SPI_Mode_TypeDef enumeration.
  * @param[in] ClockPolarity : This parameter can be any of the @ref SPI_ClockPolarity_TypeDef enumeration.
  * @param[in] ClockPhase : This parameter can be any of the @ref SPI_ClockPhase_TypeDef enumeration.
  * @param[in] Data_Direction : This parameter can be any of the @ref SPI_DataDirection_TypeDef enumeration.
  * @param[in] Slave_Management : This parameter can be any of the @ref SPI_NSS_TypeDef enumeration.
  * @param[in] CRCPolynomial : Configures the CRC polynomial.
  * @retval
  * None
  */
void SPI_Init(SPI_FirstBit_TypeDef FirstBit, SPI_BaudRatePrescaler_TypeDef BaudRatePrescaler, SPI_Mode_TypeDef Mode, SPI_ClockPolarity_TypeDef ClockPolarity, SPI_ClockPhase_TypeDef ClockPhase, SPI_DataDirection_TypeDef Data_Direction, SPI_NSS_TypeDef Slave_Management, u8 CRCPolynomial)
{
    /* Check structure elements */
    assert_param(IS_SPI_FIRSTBIT_OK(FirstBit));
    assert_param(IS_SPI_BAUDRATE_PRESCALER_OK(BaudRatePrescaler));
    assert_param(IS_SPI_MODE_OK(Mode));
    assert_param(IS_SPI_POLARITY_OK(ClockPolarity));
    assert_param(IS_SPI_PHASE_OK(ClockPhase));
    assert_param(IS_SPI_DATA_DIRECTION_OK(Data_Direction));
    assert_param(IS_SPI_SLAVEMANAGEMENT_OK(Slave_Management));
    assert_param(IS_SPI_CRC_POLYNOMIAL_OK(CRCPolynomial));

    /* Frame Format, BaudRate, Clock Polarity and Phase configuration */
    SPI->CR1 = (u8)((u8)(FirstBit) |
                    (u8)(BaudRatePrescaler) |
                    (u8)(ClockPolarity) |
                    (u8)(ClockPhase));

    /* Data direction configuration: BDM, BDOE and RXONLY bits */
    SPI->CR2 = (u8)((u8)(Data_Direction) | (u8)(Slave_Management));

    if (Mode == SPI_MODE_MASTER)
    {
        SPI->CR2 |= (u8)SPI_CR2_SSI;
    }
    else
    {
        SPI->CR2 &= (u8)~(SPI_CR2_SSI);
    }

    /* Master/Slave mode configuration */
    SPI->CR1 |= (u8)(Mode);

    /* CRC configuration */
    SPI->CRCPR = (u8)CRCPolynomial;
}

/**
  * @brief Enables or disables the SPI peripheral.
  * @param[in] NewState New state of the SPI peripheral.
  * This parameter can be:
  * - ENABLE
  * - DISABLE
  * @retval
  * None
  */
void SPI_Cmd(FunctionalState NewState)
{
    /* Check function parameters */
    assert_param(IS_FUNCTIONALSTATE_OK(NewState));

    if (NewState != DISABLE)
    {
        SPI->CR1 |= SPI_CR1_SPE; /* Enable the SPI peripheral*/
    }
    else
    {
        SPI->CR1 &= (u8)(~SPI_CR1_SPE); /* Disable the SPI peripheral*/
    }
}
/**
  * @brief Enables or disables the specified interrupts.
  * @param[in] SPI_IT Specifies the SPI interrupts sources to be enabled or disabled.
  * @param[in] NewState: The new state of the specified SPI interrupts.
  * This parameter can be:
  * - ENABLE
  * - DISABLE.
  * @retval
  * None
  */
void SPI_ITConfig(SPI_IT_TypeDef SPI_IT, FunctionalState NewState)
{
    u8 itpos = 0;
    /* Check function parameters */
    assert_param(IS_SPI_CONFIG_IT_OK(SPI_IT));
    assert_param(IS_FUNCTIONALSTATE_OK(NewState));

    /* Get the SPI IT index */
    itpos = (u8)((u8)1 << (u8)((u8)SPI_IT & (u8)0x0F));

    if (NewState != DISABLE)
    {
        SPI->ICR |= itpos; /* Enable interrupt*/
    }
    else
    {
        SPI->ICR &= (u8)(~itpos); /* Disable interrupt*/
    }
}
/**
  * @brief Transmits a Data through the SPI peripheral.
  * @param[in] Data Byte to be transmitted.
  * @retval
  * None
  */
void SPI_SendData(u8 Data)
{
    SPI->DR = Data; /* Write in the DR register the data to be sent*/
}

/**
  * @brief Returns the most recent received data by the SPI peripheral.
  * @par Parameters:
  * None
  * @retval u8 The value of the received data.
  */
u8 SPI_ReceiveData(void)
{
    return ((u8)SPI->DR); /* Return the data in the DR register*/
}

/**
  * @brief Configures internally by software the NSS pin.
  * @param[in] NewState Indicates the new state of the SPI Software slave management.
  * This parameter can be:
  * - ENABLE
  * - DISABLE
  * @retval
  * None
  */
void SPI_NSSInternalSoftwareCmd(FunctionalState NewState)
{
    /* Check function parameters */
    assert_param(IS_FUNCTIONALSTATE_OK(NewState));

    if (NewState != DISABLE)
    {
        SPI->CR2 |= SPI_CR2_SSI; /* Set NSS pin internally by software*/
    }
    else
    {
        SPI->CR2 &= (u8)(~SPI_CR2_SSI); /* Reset NSS pin internally by software*/
    }
}

/**
  * @brief Enables the transmit of the CRC value.
  * @par Parameters:
  * None
  * @retval
  * None
  */
void SPI_TransmitCRC(void)
{
    SPI->CR2 |= SPI_CR2_CRCNEXT; /* Enable the CRC transmission*/
}

/**
  * @brief Enables or disables the CRC value calculation of the transfered bytes.
  * @param[in] NewState Indicates the new state of the SPI CRC value calculation.
  * This parameter can be:
  * - ENABLE
  * - DISABLE
  * @retval
  * None
  */
void SPI_CalculateCRCCmd(FunctionalState NewState)
{
    /* Check function parameters */
    assert_param(IS_FUNCTIONALSTATE_OK(NewState));

    /* SPI must be disable forcorrect operation od Hardware CRC calculation */
    SPI_Cmd(DISABLE);

    if (NewState != DISABLE)
    {
        SPI->CR2 |= SPI_CR2_CRCEN; /* Enable the CRC calculation*/
    }
    else
    {
        SPI->CR2 &= (u8)(~SPI_CR2_CRCEN); /* Disable the CRC calculation*/
    }
}

/**
  * @brief Returns the transmit or the receive CRC register value.
  * @param[in] SPI_CRC Specifies the CRC register to be read.
  * @retval u8 The selected CRC register value.
  */
u8 SPI_GetCRC(SPI_CRC_TypeDef SPI_CRC)
{
    u8 crcreg = 0;

    /* Check function parameters */
    assert_param(IS_SPI_CRC_OK(SPI_CRC));

    if (SPI_CRC != SPI_CRC_RX)
    {
        crcreg = SPI->TXCRCR;  /* Get the Tx CRC register*/
    }
    else
    {
        crcreg = SPI->RXCRCR; /* Get the Rx CRC register*/
    }

    /* Return the selected CRC register status*/
    return crcreg;
}

/**
  * @brief Reset the Rx CRCR and Tx CRCR registers.
  * @par Parameters:
  * None
  * @retval
  * None
  */
void SPI_ResetCRC(void)
{
    /* Rx CRCR & Tx CRCR registers are reset when CRCEN (hardware calculation)
       bit in SPI_CR2 is written to 1 (enable) */
    SPI_CalculateCRCCmd(ENABLE);

    /* Previous function disable the SPI */
    SPI_Cmd(ENABLE);
}

/**
  * @brief Returns the CRC Polynomial register value.
  * @par Parameters:
  * None
  * @retval u8 The CRC Polynomial register value.
  */
u8 SPI_GetCRCPolynomial(void)
{
    return SPI->CRCPR; /* Return the CRC polynomial register */
}

/**
  * @brief Selects the data transfer direction in bi-directional mode.
  * @param[in] SPI_Direction Specifies the data transfer direction in bi-directional mode.
  * @retval
  * None
  */
void SPI_BiDirectionalLineConfig(SPI_Direction_TypeDef SPI_Direction)
{
    /* Check function parameters */
    assert_param(IS_SPI_DIRECTION_OK(SPI_Direction));

    if (SPI_Direction != SPI_DIRECTION_RX)
    {
        SPI->CR2 |= SPI_CR2_BDOE; /* Set the Tx only mode*/
    }
    else
    {
        SPI->CR2 &= (u8)(~SPI_CR2_BDOE); /* Set the Rx only mode*/
    }
}

/**
  * @brief Checks whether the specified SPI flag is set or not.
  * @param[in] SPI_FLAG : Specifies the flag to check.
  * This parameter can be any of the @ref SPI_Flag_TypeDef enumeration.
  * @retval FlagStatus : Indicates the state of SPI_FLAG.
  * This parameter can be any of the @ref FlagStatus enumeration.
  */

FlagStatus SPI_GetFlagStatus(SPI_Flag_TypeDef SPI_FLAG)
{
    FlagStatus status = RESET;
    /* Check parameters */
    assert_param(IS_SPI_FLAGS_OK(SPI_FLAG));

    /* Check the status of the specified SPI flag */
    if ((SPI->SR & (u8)SPI_FLAG) != (u8)RESET)
    {
        status = SET; /* SPI_FLAG is set */
    }
    else
    {
        status = RESET; /* SPI_FLAG is reset*/
    }

    /* Return the SPI_FLAG status */
    return status;
}

/**
  * @brief Clears the SPI flags.
  * @param[in] SPI_FLAG : Specifies the flag to clear.
  * This parameter can be one of the following values:
  * - SPI_FLAG_CRCERR
  * - SPI_FLAG_WKUP
  * @par Notes
  * - OVR (OverRun Error) interrupt pending bit is cleared by software sequence:
  *   a read operation to SPI_DR register (SPI_ReceiveData()) followed by
  *   a read operation to SPI_SR register (SPI_GetFlagStatus()).
  * - MODF (Mode Fault) interrupt pending bit is cleared by software sequence:
  *   a read/write operation to SPI_SR register (SPI_GetFlagStatus()) followed by
  *   a write operation to SPI_CR1 register (SPI_Cmd() to enable the SPI).
  * @retval
  * None
  */
void SPI_ClearFlag(SPI_Flag_TypeDef SPI_FLAG)
{
    assert_param(IS_SPI_CLEAR_FLAGS_OK(SPI_FLAG));
    /* Clear the flag bit */
    SPI->SR = (u8)(~SPI_FLAG);
}

/**
  * @brief Checks whether the specified interrupt has occurred or not.
  * @param[in] SPI_IT: Specifies the SPI interrupt pending bit to check.
  * This parameter can be one of the following values:
  * - SPI_IT_CRCERR
  * - SPI_IT_WKUP
  * - SPI_IT_OVR
  * - SPI_IT_MODF
  * - SPI_IT_RXNE
  * - SPI_IT_TXE
  * @retval ITStatus : Indicates the state of the SPI_IT.
  * This parameter can be any of the @ref ITStatus enumeration.
  */
ITStatus SPI_GetITStatus(SPI_IT_TypeDef SPI_IT)
{
    ITStatus pendingbitstatus = RESET;
    u8 itpos = 0;
    u8 itmask1 = 0;
    u8 itmask2 = 0;
    u8 enablestatus = 0;
    assert_param(IS_SPI_GET_IT_OK(SPI_IT));
    /* Get the SPI IT index */
    itpos = (u8)((u8)1 << ((u8)SPI_IT & (u8)0x0F));

    /* Get the SPI IT mask */
    itmask1 = (u8)((u8)SPI_IT >> (u8)4);
    /* Set the IT mask */
    itmask2 = (u8)((u8)1 << itmask1);
    /* Get the SPI_ITPENDINGBIT enable bit status */
    enablestatus = (u8)((u8)SPI->SR & itmask2);
    /* Check the status of the specified SPI interrupt */
    if (((SPI->ICR & itpos) != RESET) && enablestatus)
    {
        /* SPI_ITPENDINGBIT is set */
        pendingbitstatus = SET;
    }
    else
    {
        /* SPI_ITPENDINGBIT is reset */
        pendingbitstatus = RESET;
    }
    /* Return the SPI_ITPENDINGBIT status */
    return  pendingbitstatus;
}
/**
  * @brief Clears the interrupt pending bits.
  * @param[in] SPI_IT: Specifies the interrupt pending bit to clear.
  * This parameter can be one of the following values:
  * - SPI_IT_CRCERR
  * - SPI_IT_WKUP
  * @par Notes
  *    - OVR (OverRun Error) interrupt pending bit is cleared by software sequence:
  *      a read operation to SPI_DR register (SPI_ReceiveData()) followed by
  *      a read operation to SPI_SR register (SPI_GetITStatus()).
  *    - MODF (Mode Fault) interrupt pending bit is cleared by software sequence:
  *      a read/write operation to SPI_SR register (SPI_GetITStatus()) followed by
  *      a write operation to SPI_CR1 register (SPI_Cmd() to enable the SPI).
  * @retval
  * None
  */
void SPI_ClearITPendingBit(SPI_IT_TypeDef SPI_IT)
{
    u8 itpos = 0;
    assert_param(IS_SPI_CLEAR_IT_OK(SPI_IT));

    /* Clear  SPI_IT_CRCERR or SPI_IT_WKUP interrupt pending bits */

    /* Get the SPI pending bit index */
    itpos = (u8)((u8)1 << (((u8)SPI_IT & (u8)0xF0) >> 4));
    /* Clear the pending bit */
    SPI->SR = (u8)(~itpos);

}
/**
  * @}
  */

/******************* (C) COPYRIGHT 2009 STMicroelectronics *****END OF FILE****/