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/******************** (C) COPYRIGHT 2007 STMicroelectronics ********************

* File Name          : stm32f10x_can.c

* Author             : MCD Application Team

* Date First Issued  : 09/29/2006

* Description        : This file provides all the CAN firmware functions.

********************************************************************************

* History:

* 04/02/2007: V0.2

* 02/05/2007: V0.1

* 09/29/2006: V0.01

********************************************************************************

* THE PRESENT SOFTWARE 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 SOFTWARE AND/OR THE USE MADE BY CUSTOMERS OF THE CODING

* INFORMATION CONTAINED HEREIN IN CONNECTION WITH THEIR PRODUCTS.

*******************************************************************************/

/* Includes ------------------------------------------------------------------*/

#include "stm32f10x_can.h"

#include "stm32f10x_rcc.h"

/* Private typedef -----------------------------------------------------------*/

/* Private define ------------------------------------------------------------*/

/* CAN Master Control Register bits */

#define CAN_MCR_INRQ     ((u32)0x00000001) /* Initialization request */

#define CAN_MCR_SLEEP    ((u32)0x00000002) /* Sleep mode request */

#define CAN_MCR_TXFP     ((u32)0x00000004) /* Transmit FIFO priority */

#define CAN_MCR_RFLM     ((u32)0x00000008) /* Receive FIFO locked mode */

#define CAN_MCR_NART     ((u32)0x00000010) /* No automatic retransmission */

#define CAN_MCR_AWUM     ((u32)0x00000020) /* Automatic wake up mode */

#define CAN_MCR_ABOM     ((u32)0x00000040) /* Automatic bus-off management */

#define CAN_MCR_TTCM     ((u32)0x00000080) /* time triggered communication */

/* CAN Master Status Register bits */

#define CAN_MSR_INAK     ((u32)0x00000001)    /* Initialization acknowledge */

#define CAN_MSR_WKUI     ((u32)0x00000008)    /* Wake-up interrupt */

#define CAN_MSR_SLAKI    ((u32)0x00000010)    /* Sleep acknowledge interrupt */

/* CAN Transmit Status Register bits */

#define CAN_TSR_RQCP0    ((u32)0x00000001)    /* Request completed mailbox0 */

#define CAN_TSR_TXOK0    ((u32)0x00000002)    /* Transmission OK of mailbox0 */

#define CAN_TSR_ABRQ0    ((u32)0x00000080)    /* Abort request for mailbox0 */

#define CAN_TSR_RQCP1    ((u32)0x00000100)    /* Request completed mailbox1 */

#define CAN_TSR_TXOK1    ((u32)0x00000200)    /* Transmission OK of mailbox1 */

#define CAN_TSR_ABRQ1    ((u32)0x00008000)    /* Abort request for mailbox1 */

#define CAN_TSR_RQCP2    ((u32)0x00010000)    /* Request completed mailbox2 */

#define CAN_TSR_TXOK2    ((u32)0x00020000)    /* Transmission OK of mailbox2 */

#define CAN_TSR_ABRQ2    ((u32)0x00800000)    /* Abort request for mailbox2 */

#define CAN_TSR_TME0     ((u32)0x04000000)    /* Transmit mailbox 0 empty */

#define CAN_TSR_TME1     ((u32)0x08000000)    /* Transmit mailbox 1 empty */

#define CAN_TSR_TME2     ((u32)0x10000000)    /* Transmit mailbox 2 empty */

/* CAN Receive FIFO 0 Register bits */

#define CAN_RF0R_FULL0   ((u32)0x00000008)    /* FIFO 0 full */

#define CAN_RF0R_FOVR0   ((u32)0x00000010)    /* FIFO 0 overrun */

#define CAN_RF0R_RFOM0   ((u32)0x00000020)    /* Release FIFO 0 output mailbox */

/* CAN Receive FIFO 1 Register bits */

#define CAN_RF1R_FULL1   ((u32)0x00000008)    /* FIFO 1 full */

#define CAN_RF1R_FOVR1   ((u32)0x00000010)    /* FIFO 1 overrun */

#define CAN_RF1R_RFOM1   ((u32)0x00000020)    /* Release FIFO 1 output mailbox */

/* CAN Error Status Register bits */

#define CAN_ESR_EWGF     ((u32)0x00000001)    /* Error warning flag */

#define CAN_ESR_EPVF     ((u32)0x00000002)    /* Error passive flag */

#define CAN_ESR_BOFF     ((u32)0x00000004)    /* Bus-off flag */

/* CAN Mailbox Transmit Request */

#define CAN_TMIDxR_TXRQ    ((u32)0x00000001) /* Transmit mailbox request */

/* CAN Filter Master Register bits */

#define CAN_FMR_FINIT ((u32)0x00000001) /* Filter init mode */

/* Private macro -------------------------------------------------------------*/

/* Private variables ---------------------------------------------------------*/

/* Private function prototypes -----------------------------------------------*/

static ITStatus CheckITStatus(u32 CAN_Reg, u32 It_Bit);

/* Private functions ---------------------------------------------------------*/

/*******************************************************************************

* Function Name  : CAN_DeInit

* Description    : Deinitializes the CAN peripheral registers to their default

*                  reset values.

* Input          : None.

* Output         : None.

* Return         : None.

*******************************************************************************/

void CAN_DeInit(void)

{

  /* Enable CAN reset state */

  RCC_APB1PeriphResetCmd(RCC_APB1Periph_CAN, ENABLE);

  /* Release CAN from reset state */

  RCC_APB1PeriphResetCmd(RCC_APB1Periph_CAN, DISABLE);

}

/*******************************************************************************

* Function Name  : CAN_Init

* Description    : Initializes the CAN peripheral according to the specified

*                  parameters in the CAN_InitStruct.

* Input          : CAN_InitStruct: pointer to a CAN_InitTypeDef structure that

                   contains the configuration information for the CAN peripheral.

* Output         : None.

* Return         : Constant indicates initialization succeed which will be

*                  CANINITFAILED or CANINITOK.

*******************************************************************************/

u8 CAN_Init(CAN_InitTypeDef* CAN_InitStruct)

{

  u8 InitStatus = 0;

  /* Check the parameters */

  assert(IS_FUNCTIONAL_STATE(CAN_InitStruct->CAN_TTCM));

  assert(IS_FUNCTIONAL_STATE(CAN_InitStruct->CAN_ABOM));

  assert(IS_FUNCTIONAL_STATE(CAN_InitStruct->CAN_AWUM));

  assert(IS_FUNCTIONAL_STATE(CAN_InitStruct->CAN_NART));

  assert(IS_FUNCTIONAL_STATE(CAN_InitStruct->CAN_RFLM));

  assert(IS_FUNCTIONAL_STATE(CAN_InitStruct->CAN_TXFP));

  assert(IS_CAN_MODE(CAN_InitStruct->CAN_Mode));

  assert(IS_CAN_SJW(CAN_InitStruct->CAN_SJW));

  assert(IS_CAN_BS1(CAN_InitStruct->CAN_BS1));

  assert(IS_CAN_BS2(CAN_InitStruct->CAN_BS2));

  assert(IS_CAN_CLOCK(CAN_InitStruct->CAN_Clock));

  assert(IS_CAN_PRESCALER(CAN_InitStruct->CAN_Prescaler));

  /* Request initialisation */

  CAN->MCR = CAN_MCR_INRQ;

  /* ...and check acknowledged */

  if ((CAN->MSR & CAN_MSR_INAK) == 0)

  {

    InitStatus = CANINITFAILED;

  }

  else

  {

    /* Set the time triggered communication mode */

    if (CAN_InitStruct->CAN_TTCM == ENABLE)

    {

      CAN->MCR |= CAN_MCR_TTCM;

    }

    else

    {

      CAN->MCR &= ~CAN_MCR_TTCM;

    }

    /* Set the automatic bus-off management */

    if (CAN_InitStruct->CAN_ABOM == ENABLE)

    {

      CAN->MCR |= CAN_MCR_ABOM;

    }

    else

    {

      CAN->MCR &= ~CAN_MCR_ABOM;

    }

    /* Set the automatic wake-up mode */

    if (CAN_InitStruct->CAN_AWUM == ENABLE)

    {

      CAN->MCR |= CAN_MCR_AWUM;

    }

    else

    {

      CAN->MCR &= ~CAN_MCR_AWUM;

    }

    /* Set the no automatic retransmission */

    if (CAN_InitStruct->CAN_NART == ENABLE)

    {

      CAN->MCR |= CAN_MCR_NART;

    }

    else

    {

      CAN->MCR &= ~CAN_MCR_NART;

    }

    /* Set the receive FIFO locked mode */

    if (CAN_InitStruct->CAN_RFLM == ENABLE)

    {

      CAN->MCR |= CAN_MCR_RFLM;

    }

    else

    {

      CAN->MCR &= ~CAN_MCR_RFLM;

    }

    /* Set the transmit FIFO priority */

    if (CAN_InitStruct->CAN_TXFP == ENABLE)

    {

      CAN->MCR |= CAN_MCR_TXFP;

    }

    else

    {

      CAN->MCR &= ~CAN_MCR_TXFP;

    }

    /* Set the bit timing register */

    CAN->BTR = (u32)((u32)CAN_InitStruct->CAN_Mode << 30) | ((u32)CAN_InitStruct->CAN_SJW << 24) |

               ((u32)CAN_InitStruct->CAN_BS1 << 16) | ((u32)CAN_InitStruct->CAN_BS2 << 20) |

               ((u32)CAN_InitStruct->CAN_Clock << 15) | ((u32)CAN_InitStruct->CAN_Prescaler - 1);

    InitStatus = CANINITOK;

    /* Request leave initialisation */

    CAN->MCR &= ~CAN_MCR_INRQ;

    /* ...and check acknowledged */

    if ((CAN->MSR & CAN_MSR_INAK) != CAN_MSR_INAK)

    {

      InitStatus = CANINITFAILED;

    }

  }

  /* At this step, return the status of initialization */

  return InitStatus;

}

/*******************************************************************************

* Function Name  : CAN_FilterInit

* Description    : Initializes the CAN peripheral according to the specified

*                  parameters in the CAN_FilterInitStruct.

* Input          : CAN_FilterInitStruct: pointer to a CAN_FilterInitTypeDef

*                  structure that contains the configuration information.

* Output         : None.

* Return         : None.

*******************************************************************************/

void CAN_FilterInit(CAN_FilterInitTypeDef* CAN_FilterInitStruct)

{

  u16 FilterNumber_BitPos = 0;

  /* Check the parameters */

  assert(IS_CAN_FILTER_NUMBER(CAN_FilterInitStruct->CAN_FilterNumber));

  assert(IS_CAN_FILTER_MODE(CAN_FilterInitStruct->CAN_FilterMode));

  assert(IS_CAN_FILTER_SCALE(CAN_FilterInitStruct->CAN_FilterScale));

  assert(IS_CAN_FILTER_FIFO(CAN_FilterInitStruct->CAN_FilterFIFOAssignment));

  assert(IS_FUNCTIONAL_STATE(CAN_FilterInitStruct->CAN_FilterActivation));

  FilterNumber_BitPos = (u16)((u16)0x0001 << ((u16)CAN_FilterInitStruct->CAN_FilterNumber));

  /* Initialisation mode for the filter */

  CAN->FMR |= CAN_FMR_FINIT;

  /* Filter Deactivation */

  CAN->FA0R &= ~(u32)FilterNumber_BitPos;

  /* Filter Scale */

  if (CAN_FilterInitStruct->CAN_FilterScale == CAN_FilterScale_16bit)

  {

    /* 16-bit scale for the filter */

    CAN->FS0R &= ~(u32)FilterNumber_BitPos;

    /* First 16-bit identifier and First 16-bit mask */

    /* Or First 16-bit identifier and Second 16-bit identifier */

    CAN->sFilterRegister[CAN_FilterInitStruct->CAN_FilterNumber].FR0 = ((u32)((u32)0x0000FFFF & CAN_FilterInitStruct->CAN_FilterMaskIdLow) << 16) |

        ((u32)0x0000FFFF & CAN_FilterInitStruct->CAN_FilterIdLow);

    /* Second 16-bit identifier and Second 16-bit mask */

    /* Or Third 16-bit identifier and Fourth 16-bit identifier */

    CAN->sFilterRegister[CAN_FilterInitStruct->CAN_FilterNumber].FR1 = ((u32)((u32)0x0000FFFF & CAN_FilterInitStruct->CAN_FilterMaskIdHigh) << 16) |

        ((u32)0x0000FFFF & CAN_FilterInitStruct->CAN_FilterIdHigh);

  }

  if (CAN_FilterInitStruct->CAN_FilterScale == CAN_FilterScale_32bit)

  {

    /* 32-bit scale for the filter */

    CAN->FS0R |= FilterNumber_BitPos;

    /* 32-bit identifier or First 32-bit identifier */

    CAN->sFilterRegister[CAN_FilterInitStruct->CAN_FilterNumber].FR0 = ((u32)((u32)0x0000FFFF & CAN_FilterInitStruct->CAN_FilterIdHigh) << 16) |

        ((u32)0x0000FFFF & CAN_FilterInitStruct->CAN_FilterIdLow);

    /* 32-bit mask or Second 32-bit identifier */

    CAN->sFilterRegister[CAN_FilterInitStruct->CAN_FilterNumber].FR1 = ((u32)((u32)0x0000FFFF & CAN_FilterInitStruct->CAN_FilterMaskIdHigh) << 16) |

        ((u32)0x0000FFFF & CAN_FilterInitStruct->CAN_FilterMaskIdLow);

  }

  /* Filter Mode */

  if (CAN_FilterInitStruct->CAN_FilterMode == CAN_FilterMode_IdMask)

  {

    /*Id/Mask mode for the filter*/

    CAN->FM0R &= ~(u32)FilterNumber_BitPos;

  }

  else /* CAN_FilterInitStruct->CAN_FilterMode == CAN_FilterMode_IdList */

  {

    /*Identifier list mode for the filter*/

    CAN->FM0R |= (u32)FilterNumber_BitPos;

  }

  /* Filter FIFO assignment */

  if (CAN_FilterInitStruct->CAN_FilterFIFOAssignment == CAN_FilterFIFO0)

  {

    /* FIFO 0 assignation for the filter */

    CAN->FFA0R &= ~(u32)FilterNumber_BitPos;

  }

  if (CAN_FilterInitStruct->CAN_FilterFIFOAssignment == CAN_FilterFIFO1)

  {

    /* FIFO 1 assignation for the filter */

    CAN->FFA0R |= (u32)FilterNumber_BitPos;

  }

  /* Filter activation */

  if (CAN_FilterInitStruct->CAN_FilterActivation == ENABLE)

  {

    CAN->FA0R |= FilterNumber_BitPos;

  }

  /* Leave the initialisation mode for the filter */

  CAN->FMR &= ~CAN_FMR_FINIT;

}

/*******************************************************************************

* Function Name  : CAN_StructInit

* Description    : Fills each CAN_InitStruct member with its default value.

* Input          : CAN_InitStruct: pointer to a CAN_InitTypeDef structure which

*                  will be initialized.

* Output         : None.

* Return         : None.

*******************************************************************************/

void CAN_StructInit(CAN_InitTypeDef* CAN_InitStruct)

{

  /* Reset CAN init structure parameters values */

  /* Initialize the time triggered communication mode */

  CAN_InitStruct->CAN_TTCM = DISABLE;

  /* Initialize the automatic bus-off management */

  CAN_InitStruct->CAN_ABOM = DISABLE;

  /* Initialize the automatic wake-up mode */

  CAN_InitStruct->CAN_AWUM = DISABLE;

  /* Initialize the no automatic retransmission */

  CAN_InitStruct->CAN_NART = DISABLE;

  /* Initialize the receive FIFO locked mode */

  CAN_InitStruct->CAN_RFLM = DISABLE;

  /* Initialize the transmit FIFO priority */

  CAN_InitStruct->CAN_TXFP = DISABLE;

  /* Initialize the CAN_Mode member */

  CAN_InitStruct->CAN_Mode = CAN_Mode_Normal;

  /* Initialize the CAN_SJW member */

  CAN_InitStruct->CAN_SJW = CAN_SJW_0tq;

  /* Initialize the CAN_BS1 member */

  CAN_InitStruct->CAN_BS1 = CAN_BS1_4tq;

  /* Initialize the CAN_BS2 member */

  CAN_InitStruct->CAN_BS2 = CAN_BS2_3tq;

  /* Initialize the CAN_Clock member */

  CAN_InitStruct->CAN_Clock = CAN_Clock_APB;

  /* Initialize the CAN_Prescaler member */

  CAN_InitStruct->CAN_Prescaler = 1;

}

/*******************************************************************************

* Function Name  : CAN_ITConfig

* Description    : Enables or disables the CAN interrupts.

* Input          : - CAN_IT: specifies the CAN interrupt sources to be enabled or

*                    disabled.

*                  - NewState: new state of the CAN interrupts.

*                    This parameter can be: ENABLE or DISABLE.

* Output         : None.

* Return         : None.

*******************************************************************************/

void CAN_ITConfig(u32 CAN_IT, FunctionalState NewState)

{

  /* Check the parameters */

  assert(IS_CAN_IT(CAN_IT));

  assert(IS_FUNCTIONAL_STATE(NewState));

  if (NewState != DISABLE)

  {

    /* Enable the selected CAN interrupt */

    CAN->IER |= CAN_IT;

  }

  else

  {

    /* Disable the selected CAN interrupt */

    CAN->IER &= ~CAN_IT;

  }

}

/*******************************************************************************

* Function Name  : CAN_Transmit

* Description    : Initiates the transmission of a message.

* Input          : TxMessage: pointer to a structure which contains CAN Id, CAN

*                  DLC and CAN datas.

* Output         : None.

* Return         : The number of the mailbox that is used for transmission

*                  or CAN_NO_MB if there is no empty mailbox.

*******************************************************************************/

u8 CAN_Transmit(CanTxMsg* TxMessage)

{

  u8 TransmitMailbox = 0;

  /* Check the parameters */

  assert(IS_CAN_STDID(TxMessage->StdId));

  assert(IS_CAN_EXTID(TxMessage->StdId));

  assert(IS_CAN_IDTYPE(TxMessage->IDE));

  assert(IS_CAN_RTR(TxMessage->RTR));

  assert(IS_CAN_DLC(TxMessage->DLC));

  /* Select one empty transmit mailbox */

  if ((CAN->TSR&CAN_TSR_TME0) == CAN_TSR_TME0)

  {

    TransmitMailbox = 0;

  }

  else if ((CAN->TSR&CAN_TSR_TME1) == CAN_TSR_TME1)

  {

    TransmitMailbox = 1;

  }

  else if ((CAN->TSR&CAN_TSR_TME2) == CAN_TSR_TME2)

  {

    TransmitMailbox = 2;

  }

  else

  {

    TransmitMailbox = CAN_NO_MB;

  }

  if (TransmitMailbox != CAN_NO_MB)

  {

    /* Set up the Id */

    TxMessage->StdId &= (u32)0x000007FF;

    TxMessage->StdId = TxMessage->StdId << 21;

    TxMessage->ExtId &= (u32)0x0003FFFF;

    TxMessage->ExtId <<= 3;

    CAN->sTxMailBox[TransmitMailbox].TIR &= CAN_TMIDxR_TXRQ;

    CAN->sTxMailBox[TransmitMailbox].TIR |= (TxMessage->StdId | TxMessage->ExtId |

                                            TxMessage->IDE | TxMessage->RTR);

    /* Set up the DLC */

    TxMessage->DLC &= (u8)0x0000000F;

    CAN->sTxMailBox[TransmitMailbox].TDTR &= (u32)0xFFFFFFF0;

    CAN->sTxMailBox[TransmitMailbox].TDTR |= TxMessage->DLC;

    /* Set up the data field */

    CAN->sTxMailBox[TransmitMailbox].TDLR = (((u32)TxMessage->Data[3] << 24) | ((u32)TxMessage->Data[2] << 16) |

                                            ((u32)TxMessage->Data[1] << 8) | ((u32)TxMessage->Data[0]));

    CAN->sTxMailBox[TransmitMailbox].TDHR = (((u32)TxMessage->Data[7] << 24) | ((u32)TxMessage->Data[6] << 16) |

                                            ((u32)TxMessage->Data[5] << 8) | ((u32)TxMessage->Data[4]));

    /* Request transmission */

    CAN->sTxMailBox[TransmitMailbox].TIR |= CAN_TMIDxR_TXRQ;

  }

  return TransmitMailbox;

}

/*******************************************************************************

* Function Name  : CAN_TransmitStatus

* Description    : Check the transmission of a message.

* Input          : TransmitMailbox: the number of the mailbox that is used for

*                  transmission.

* Output         : None.

* Return         : CANTXOK if the CAN driver transmits the message, CANTXFAILED

*                  in an other case.

*******************************************************************************/

u32 CAN_TransmitStatus(u8 TransmitMailbox)

{

  /* RQCP, TXOK and TME bits */

  u32 State = 0;

  /* Check the parameters */

  assert(IS_CAN_TRANSMITMAILBOX(TransmitMailbox));

  switch (TransmitMailbox)

  {

    case (0): State |= ((CAN->TSR & CAN_TSR_RQCP0) << 2);

      State |= ((CAN->TSR & CAN_TSR_TXOK0) >> 0);

      State |= ((CAN->TSR & CAN_TSR_TME0) >> 26);

      break;

    case (1): State |= ((CAN->TSR & CAN_TSR_RQCP1) >> 6);

      State |= ((CAN->TSR & CAN_TSR_TXOK1) >> 8);

      State |= ((CAN->TSR & CAN_TSR_TME1) >> 27);

      break;

    case (2): State |= ((CAN->TSR & CAN_TSR_RQCP2) >> 14);

      State |= ((CAN->TSR & CAN_TSR_TXOK2) >> 16);

      State |= ((CAN->TSR & CAN_TSR_TME2) >> 28);

      break;

    default:

      State = CANTXFAILED;

      break;

  }

  switch (State)

  {

      /* transmit pending  */

    case (0x0): State = CANTXPENDING;

      break;

      /* transmit failed  */

    case (0x5): State = CANTXFAILED;

      break;

      /* transmit succedeed  */

    case (0x7): State = CANTXOK;

      break;

    default:

      State = CANTXFAILED;

      break;

  }

  return State;

}

/*******************************************************************************

* Function Name  : CAN_CancelTransmit

* Description    : Cancels a transmit request.

* Input          : Mailbox number.

* Output         : None.

* Return         : None.

*******************************************************************************/

void CAN_CancelTransmit(u8 Mailbox)

{

  /* Check the parameters */

  assert(IS_CAN_TRANSMITMAILBOX(Mailbox));

  /* abort transmission */

  switch (Mailbox)

  {

    case (0): CAN->TSR |= CAN_TSR_ABRQ0;

      break;

    case (1): CAN->TSR |= CAN_TSR_ABRQ1;

      break;

    case (2): CAN->TSR |= CAN_TSR_ABRQ2;

      break;

    default:

      break;

  }

}

/*******************************************************************************

* Function Name  : CAN_FIFORelease

* Description    : Release a FIFO.

* Input          : FIFONumber: FIFO to release, CAN_FIFO0 or CAN_FIFO1.

* Output         : None.

* Return         : None.

*******************************************************************************/

void CAN_FIFORelease(u8 FIFONumber)

{

  /* Check the parameters */

  assert(IS_CAN_FIFO(FIFONumber));

  /* Release FIFO0 */

  if (FIFONumber == CAN_FIFO0)

  {

    CAN->RF0R = CAN_RF0R_RFOM0;

  }

  /* Release FIFO1 */

  else /* FIFONumber == CAN_FIFO1 */

  {

    CAN->RF1R = CAN_RF1R_RFOM1;

  }

}

/*******************************************************************************

* Function Name  : CAN_MessagePending

* Description    : Return the number of pending messages.

* Input          : FIFONumber: Receive FIFO number, CAN_FIFO0 or CAN_FIFO1.

* Output         : None.

* Return         : NbMessage which is the number of pending message.

*******************************************************************************/

u8 CAN_MessagePending(u8 FIFONumber)

{

  u8 MessagePending=0;

  /* Check the parameters */

  assert(IS_CAN_FIFO(FIFONumber));

  if (FIFONumber == CAN_FIFO0)

  {

    MessagePending = (u8)(CAN->RF0R&(u32)0x03);

  }

  else if (FIFONumber == CAN_FIFO1)

  {

    MessagePending = (u8)(CAN->RF1R&(u32)0x03);

  }

  else

  {

    MessagePending = 0;

  }

  return MessagePending;

}

/*******************************************************************************

* Function Name  : CAN_Receive

* Description    : Receives a message.

* Input          : FIFONumber: Receive FIFO number, CAN_FIFO0 or CAN_FIFO1.

* Output         : RxMessage: pointer to a structure which contains CAN Id,

*                  CAN DLC, CAN datas and FMI number.

* Return         : None.

*******************************************************************************/

void CAN_Receive(u8 FIFONumber, CanRxMsg* RxMessage)

{

  /* Check the parameters */

  assert(IS_CAN_FIFO(FIFONumber));

  /* Get the Id */

  RxMessage->StdId = (u32)0x000007FF & (CAN->sFIFOMailBox[FIFONumber].RIR >> 21);

  RxMessage->ExtId = (u32)0x0003FFFF & (CAN->sFIFOMailBox[FIFONumber].RIR >> 3);

  RxMessage->IDE = (u32)0x00000004 & CAN->sFIFOMailBox[FIFONumber].RIR;

  RxMessage->RTR = (u32)0x00000002 & CAN->sFIFOMailBox[FIFONumber].RIR;

  /* Get the DLC */

  RxMessage->DLC = (u32)0x0000000F & CAN->sFIFOMailBox[FIFONumber].RDTR;

  /* Get the FMI */

  RxMessage->FMI = (u32)0x000000FF & (CAN->sFIFOMailBox[FIFONumber].RDTR >> 8);

  /* Get the data field */

  RxMessage->Data[0] = (u32)0x000000FF & CAN->sFIFOMailBox[FIFONumber].RDLR;

  RxMessage->Data[1] = (u32)0x000000FF & (CAN->sFIFOMailBox[FIFONumber].RDLR >> 8);

  RxMessage->Data[2] = (u32)0x000000FF & (CAN->sFIFOMailBox[FIFONumber].RDLR >> 16);

  RxMessage->Data[3] = (u32)0x000000FF & (CAN->sFIFOMailBox[FIFONumber].RDLR >> 24);

  RxMessage->Data[4] = (u32)0x000000FF & CAN->sFIFOMailBox[FIFONumber].RDHR;

  RxMessage->Data[5] = (u32)0x000000FF & (CAN->sFIFOMailBox[FIFONumber].RDHR >> 8);

  RxMessage->Data[6] = (u32)0x000000FF & (CAN->sFIFOMailBox[FIFONumber].RDHR >> 16);

  RxMessage->Data[7] = (u32)0x000000FF & (CAN->sFIFOMailBox[FIFONumber].RDHR >> 24);

  /* Release the FIFO */

  CAN_FIFORelease(FIFONumber);

}

/*******************************************************************************

* Function Name  : CAN_Sleep

* Description    : Enters the low power mode.

* Input          : None.

* Output         : None.

* Return         : CANSLEEPOK if sleep entered, CANSLEEPFAILED in an other case.

*******************************************************************************/

u8 CAN_Sleep(void)

{

  u8 SleepStatus = 0;

  /* Sleep mode entering request */

  CAN->MCR |= CAN_MCR_SLEEP;

  SleepStatus = CANSLEEPOK;

  /* Sleep mode status */

  if ((CAN->MCR&CAN_MCR_SLEEP) == 0)

  {

    /* Sleep mode not entered */

    SleepStatus = CANSLEEPFAILED;

  }

  /* At this step, sleep mode status */

  return SleepStatus;

}

/*******************************************************************************

* Function Name  : CAN_WakeUp

* Description    : Wakes the CAN up.

* Input          : None.

* Output         : None.

* Return         : CANWAKEUPOK if sleep mode left, CANWAKEUPFAILED in an other

*                  case.

*******************************************************************************/

u8 CAN_WakeUp(void)

{

  u8 WakeUpStatus = 0;

  /* Wake up request */

  CAN->MCR &= ~CAN_MCR_SLEEP;

  WakeUpStatus = CANWAKEUPFAILED;

  /* Sleep mode status */

  if ((CAN->MCR&CAN_MCR_SLEEP) == 0)

  {

    /* Sleep mode exited */

    WakeUpStatus = CANWAKEUPOK;

  }

  /* At this step, sleep mode status */

  return WakeUpStatus;

}

/*******************************************************************************

* Function Name  : CAN_GetFlagStatus

* Description    : Checks whether the CAN flag is set or not.

* Input          : CAN_FLAG: specifies the flag to check.

* Output         : None.

* Return         : The new state of CAN_FLAG (SET or RESET).

*******************************************************************************/

FlagStatus CAN_GetFlagStatus(u32 CAN_FLAG)

{

  FlagStatus bitstatus = RESET;

  /* Check the parameters */

  assert(IS_CAN_FLAG(CAN_FLAG));

  /* Check the status of the specified CAN flag */

  if ((CAN->ESR & CAN_FLAG) != (u32)RESET)

  {

    /* CAN_FLAG is set */

    bitstatus = SET;

  }