stm32f2xx_can.c

STM32+Grlib

/**
  ******************************************************************************
  * @file    stm32f2xx_can.c
  * @author  MCD Application Team
  * @version V1.0.0
  * @date    18-April-2011
  * @brief   This file provides firmware functions to manage the following 
  *          functionalities of the Controller area network (CAN) peripheral:           
  *           - Initialization and Configuration 
  *           - CAN Frames Transmission 
  *           - CAN Frames Reception    
  *           - Operation modes switch  
  *           - Error management          
  *           - Interrupts and flags        
  *         
  *  @verbatim
  *                               
  *          ===================================================================      
  *                                   How to use this driver
  *          ===================================================================
                
  *          1.  Enable the CAN controller interface clock using 
  *                  RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN1, ENABLE); for CAN1 
  *              and RCC_APB1PeriphClockCmd(RCC_APB1Periph_CAN2, ENABLE); for CAN2
  *  @note   In case you are using CAN2 only, you have to enable the CAN1 clock.
  *     
  *          2. CAN pins configuration
  *               - Enable the clock for the CAN GPIOs using the following function:
  *                   RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOx, ENABLE);   
  *               - Connect the involved CAN pins to AF9 using the following function 
  *                   GPIO_PinAFConfig(GPIOx, GPIO_PinSourcex, GPIO_AF_CANx); 
  *                - Configure these CAN pins in alternate function mode by calling
  *                  the function  GPIO_Init();
  *    
  *          3.  Initialise and configure the CAN using CAN_Init() and 
  *               CAN_FilterInit() functions.   
  *               
  *          4.  Transmit the desired CAN frame using CAN_Transmit() function.
  *         
  *          5.  Check the transmission of a CAN frame using CAN_TransmitStatus()
  *              function.
  *               
  *          6.  Cancel the transmission of a CAN frame using CAN_CancelTransmit()
  *              function.  
  *            
  *          7.  Receive a CAN frame using CAN_Recieve() function.
  *         
  *          8.  Release the receive FIFOs using CAN_FIFORelease() function.
  *               
  *          9. Return the number of pending received frames using 
  *              CAN_MessagePending() function.            
  *                   
  *          10. To control CAN events you can use one of the following two methods:
  *               - Check on CAN flags using the CAN_GetFlagStatus() function.  
  *               - Use CAN interrupts through the function CAN_ITConfig() at 
  *                 initialization phase and CAN_GetITStatus() function into 
  *                 interrupt routines to check if the event has occurred or not.
  *             After checking on a flag you should clear it using CAN_ClearFlag()
  *             function. And after checking on an interrupt event you should 
  *             clear it using CAN_ClearITPendingBit() function.            
  *               
  *              
  *  @endverbatim
  *         
  ******************************************************************************
  * @attention
  *
  * 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 2011 STMicroelectronics</center></h2>
  ******************************************************************************  
  */

/* Includes ------------------------------------------------------------------*/
#include "stm32f2xx_can.h"
#include "stm32f2xx_rcc.h"

/** @addtogroup STM32F2xx_StdPeriph_Driver
  * @{
  */

/** @defgroup CAN 
  * @brief CAN driver modules
  * @{
  */ 
/* Private typedef -----------------------------------------------------------*/
/* Private define ------------------------------------------------------------*/

/* CAN Master Control Register bits */
#define MCR_DBF           ((uint32_t)0x00010000) /* software master reset */

/* CAN Mailbox Transmit Request */
#define TMIDxR_TXRQ       ((uint32_t)0x00000001) /* Transmit mailbox request */

/* CAN Filter Master Register bits */
#define FMR_FINIT         ((uint32_t)0x00000001) /* Filter init mode */

/* Time out for INAK bit */
#define INAK_TIMEOUT      ((uint32_t)0x0000FFFF)
/* Time out for SLAK bit */
#define SLAK_TIMEOUT      ((uint32_t)0x0000FFFF)

/* Flags in TSR register */
#define CAN_FLAGS_TSR     ((uint32_t)0x08000000) 
/* Flags in RF1R register */
#define CAN_FLAGS_RF1R    ((uint32_t)0x04000000) 
/* Flags in RF0R register */
#define CAN_FLAGS_RF0R    ((uint32_t)0x02000000) 
/* Flags in MSR register */
#define CAN_FLAGS_MSR     ((uint32_t)0x01000000) 
/* Flags in ESR register */
#define CAN_FLAGS_ESR     ((uint32_t)0x00F00000) 

/* Mailboxes definition */
#define CAN_TXMAILBOX_0   ((uint8_t)0x00)
#define CAN_TXMAILBOX_1   ((uint8_t)0x01)
#define CAN_TXMAILBOX_2   ((uint8_t)0x02) 

#define CAN_MODE_MASK     ((uint32_t) 0x00000003)

/* Private macro -------------------------------------------------------------*/
/* Private variables ---------------------------------------------------------*/
/* Private function prototypes -----------------------------------------------*/
/* Private functions ---------------------------------------------------------*/
static ITStatus CheckITStatus(uint32_t CAN_Reg, uint32_t It_Bit);

/** @defgroup CAN_Private_Functions
  * @{
  */

/** @defgroup CAN_Group1 Initialization and Configuration functions
 *  @brief    Initialization and Configuration functions 
 *
@verbatim    
 ===============================================================================
                      Initialization and Configuration functions
 ===============================================================================  
  This section provides functions allowing to 
   - Initialize the CAN peripherals : Prescaler, operating mode, the maximum number 
     of time quanta to perform resynchronization, the number of time quanta in
     Bit Segment 1 and 2 and many other modes. 
     Refer to  @ref CAN_InitTypeDef  for more details.
   - Configures the CAN reception filter.                                      
   - Select the start bank filter for slave CAN.
   - Enables or disables the Debug Freeze mode for CAN
   - Enables or disables the CAN Time Trigger Operation communication mode
   
@endverbatim
  * @{
  */
  
/**
  * @brief  Deinitializes the CAN peripheral registers to their default reset values.
  * @param  CANx: where x can be 1 or 2 to select the CAN peripheral.
  * @retval None.
  */
void CAN_DeInit(CAN_TypeDef* CANx)
{
  /* Check the parameters */
  assert_param(IS_CAN_ALL_PERIPH(CANx));
 
  if (CANx == CAN1)
  {
    /* Enable CAN1 reset state */
    RCC_APB1PeriphResetCmd(RCC_APB1Periph_CAN1, ENABLE);
    /* Release CAN1 from reset state */
    RCC_APB1PeriphResetCmd(RCC_APB1Periph_CAN1, DISABLE);
  }
  else
  {  
    /* Enable CAN2 reset state */
    RCC_APB1PeriphResetCmd(RCC_APB1Periph_CAN2, ENABLE);
    /* Release CAN2 from reset state */
    RCC_APB1PeriphResetCmd(RCC_APB1Periph_CAN2, DISABLE);
  }
}

/**
  * @brief  Initializes the CAN peripheral according to the specified
  *         parameters in the CAN_InitStruct.
  * @param  CANx: where x can be 1 or 2 to select the CAN peripheral.
  * @param  CAN_InitStruct: pointer to a CAN_InitTypeDef structure that contains
  *         the configuration information for the CAN peripheral.
  * @retval Constant indicates initialization succeed which will be 
  *         CAN_InitStatus_Failed or CAN_InitStatus_Success.
  */
uint8_t CAN_Init(CAN_TypeDef* CANx, CAN_InitTypeDef* CAN_InitStruct)
{
  uint8_t InitStatus = CAN_InitStatus_Failed;
  uint32_t wait_ack = 0x00000000;
  /* Check the parameters */
  assert_param(IS_CAN_ALL_PERIPH(CANx));
  assert_param(IS_FUNCTIONAL_STATE(CAN_InitStruct->CAN_TTCM));
  assert_param(IS_FUNCTIONAL_STATE(CAN_InitStruct->CAN_ABOM));
  assert_param(IS_FUNCTIONAL_STATE(CAN_InitStruct->CAN_AWUM));
  assert_param(IS_FUNCTIONAL_STATE(CAN_InitStruct->CAN_NART));
  assert_param(IS_FUNCTIONAL_STATE(CAN_InitStruct->CAN_RFLM));
  assert_param(IS_FUNCTIONAL_STATE(CAN_InitStruct->CAN_TXFP));
  assert_param(IS_CAN_MODE(CAN_InitStruct->CAN_Mode));
  assert_param(IS_CAN_SJW(CAN_InitStruct->CAN_SJW));
  assert_param(IS_CAN_BS1(CAN_InitStruct->CAN_BS1));
  assert_param(IS_CAN_BS2(CAN_InitStruct->CAN_BS2));
  assert_param(IS_CAN_PRESCALER(CAN_InitStruct->CAN_Prescaler));

  /* Exit from sleep mode */
  CANx->MCR &= (~(uint32_t)CAN_MCR_SLEEP);

  /* Request initialisation */
  CANx->MCR |= CAN_MCR_INRQ ;

  /* Wait the acknowledge */
  while (((CANx->MSR & CAN_MSR_INAK) != CAN_MSR_INAK) && (wait_ack != INAK_TIMEOUT))
  {
    wait_ack++;
  }

  /* Check acknowledge */
  if ((CANx->MSR & CAN_MSR_INAK) != CAN_MSR_INAK)
  {
    InitStatus = CAN_InitStatus_Failed;
  }
  else 
  {
    /* Set the time triggered communication mode */
    if (CAN_InitStruct->CAN_TTCM == ENABLE)
    {
      CANx->MCR |= CAN_MCR_TTCM;
    }
    else
    {
      CANx->MCR &= ~(uint32_t)CAN_MCR_TTCM;
    }

    /* Set the automatic bus-off management */
    if (CAN_InitStruct->CAN_ABOM == ENABLE)
    {
      CANx->MCR |= CAN_MCR_ABOM;
    }
    else
    {
      CANx->MCR &= ~(uint32_t)CAN_MCR_ABOM;
    }

    /* Set the automatic wake-up mode */
    if (CAN_InitStruct->CAN_AWUM == ENABLE)
    {
      CANx->MCR |= CAN_MCR_AWUM;
    }
    else
    {
      CANx->MCR &= ~(uint32_t)CAN_MCR_AWUM;
    }

    /* Set the no automatic retransmission */
    if (CAN_InitStruct->CAN_NART == ENABLE)
    {
      CANx->MCR |= CAN_MCR_NART;
    }
    else
    {
      CANx->MCR &= ~(uint32_t)CAN_MCR_NART;
    }

    /* Set the receive FIFO locked mode */
    if (CAN_InitStruct->CAN_RFLM == ENABLE)
    {
      CANx->MCR |= CAN_MCR_RFLM;
    }
    else
    {
      CANx->MCR &= ~(uint32_t)CAN_MCR_RFLM;
    }

    /* Set the transmit FIFO priority */
    if (CAN_InitStruct->CAN_TXFP == ENABLE)
    {
      CANx->MCR |= CAN_MCR_TXFP;
    }
    else
    {
      CANx->MCR &= ~(uint32_t)CAN_MCR_TXFP;
    }

    /* Set the bit timing register */
    CANx->BTR = (uint32_t)((uint32_t)CAN_InitStruct->CAN_Mode << 30) | \
                ((uint32_t)CAN_InitStruct->CAN_SJW << 24) | \
                ((uint32_t)CAN_InitStruct->CAN_BS1 << 16) | \
                ((uint32_t)CAN_InitStruct->CAN_BS2 << 20) | \
               ((uint32_t)CAN_InitStruct->CAN_Prescaler - 1);

    /* Request leave initialisation */
    CANx->MCR &= ~(uint32_t)CAN_MCR_INRQ;

   /* Wait the acknowledge */
   wait_ack = 0;

   while (((CANx->MSR & CAN_MSR_INAK) == CAN_MSR_INAK) && (wait_ack != INAK_TIMEOUT))
   {
     wait_ack++;
   }

    /* ...and check acknowledged */
    if ((CANx->MSR & CAN_MSR_INAK) == CAN_MSR_INAK)
    {
      InitStatus = CAN_InitStatus_Failed;
    }
    else
    {
      InitStatus = CAN_InitStatus_Success ;
    }
  }

  /* At this step, return the status of initialization */
  return InitStatus;
}

/**
  * @brief  Configures the CAN reception filter according to the specified
  *         parameters in the CAN_FilterInitStruct.
  * @param  CAN_FilterInitStruct: pointer to a CAN_FilterInitTypeDef structure that
  *         contains the configuration information.
  * @retval None
  */
void CAN_FilterInit(CAN_FilterInitTypeDef* CAN_FilterInitStruct)
{
  uint32_t filter_number_bit_pos = 0;
  /* Check the parameters */
  assert_param(IS_CAN_FILTER_NUMBER(CAN_FilterInitStruct->CAN_FilterNumber));
  assert_param(IS_CAN_FILTER_MODE(CAN_FilterInitStruct->CAN_FilterMode));
  assert_param(IS_CAN_FILTER_SCALE(CAN_FilterInitStruct->CAN_FilterScale));
  assert_param(IS_CAN_FILTER_FIFO(CAN_FilterInitStruct->CAN_FilterFIFOAssignment));
  assert_param(IS_FUNCTIONAL_STATE(CAN_FilterInitStruct->CAN_FilterActivation));

  filter_number_bit_pos = ((uint32_t)1) << CAN_FilterInitStruct->CAN_FilterNumber;

  /* Initialisation mode for the filter */
  CAN1->FMR |= FMR_FINIT;

  /* Filter Deactivation */
  CAN1->FA1R &= ~(uint32_t)filter_number_bit_pos;

  /* Filter Scale */
  if (CAN_FilterInitStruct->CAN_FilterScale == CAN_FilterScale_16bit)
  {
    /* 16-bit scale for the filter */
    CAN1->FS1R &= ~(uint32_t)filter_number_bit_pos;

    /* First 16-bit identifier and First 16-bit mask */
    /* Or First 16-bit identifier and Second 16-bit identifier */
    CAN1->sFilterRegister[CAN_FilterInitStruct->CAN_FilterNumber].FR1 = 
       ((0x0000FFFF & (uint32_t)CAN_FilterInitStruct->CAN_FilterMaskIdLow) << 16) |
        (0x0000FFFF & (uint32_t)CAN_FilterInitStruct->CAN_FilterIdLow);

    /* Second 16-bit identifier and Second 16-bit mask */
    /* Or Third 16-bit identifier and Fourth 16-bit identifier */
    CAN1->sFilterRegister[CAN_FilterInitStruct->CAN_FilterNumber].FR2 = 
       ((0x0000FFFF & (uint32_t)CAN_FilterInitStruct->CAN_FilterMaskIdHigh) << 16) |
        (0x0000FFFF & (uint32_t)CAN_FilterInitStruct->CAN_FilterIdHigh);
  }

  if (CAN_FilterInitStruct->CAN_FilterScale == CAN_FilterScale_32bit)
  {
    /* 32-bit scale for the filter */
    CAN1->FS1R |= filter_number_bit_pos;
    /* 32-bit identifier or First 32-bit identifier */
    CAN1->sFilterRegister[CAN_FilterInitStruct->CAN_FilterNumber].FR1 = 
       ((0x0000FFFF & (uint32_t)CAN_FilterInitStruct->CAN_FilterIdHigh) << 16) |
        (0x0000FFFF & (uint32_t)CAN_FilterInitStruct->CAN_FilterIdLow);
    /* 32-bit mask or Second 32-bit identifier */
    CAN1->sFilterRegister[CAN_FilterInitStruct->CAN_FilterNumber].FR2 = 
       ((0x0000FFFF & (uint32_t)CAN_FilterInitStruct->CAN_FilterMaskIdHigh) << 16) |
        (0x0000FFFF & (uint32_t)CAN_FilterInitStruct->CAN_FilterMaskIdLow);
  }

  /* Filter Mode */
  if (CAN_FilterInitStruct->CAN_FilterMode == CAN_FilterMode_IdMask)
  {
    /*Id/Mask mode for the filter*/
    CAN1->FM1R &= ~(uint32_t)filter_number_bit_pos;
  }
  else /* CAN_FilterInitStruct->CAN_FilterMode == CAN_FilterMode_IdList */
  {
    /*Identifier list mode for the filter*/
    CAN1->FM1R |= (uint32_t)filter_number_bit_pos;
  }

  /* Filter FIFO assignment */
  if (CAN_FilterInitStruct->CAN_FilterFIFOAssignment == CAN_Filter_FIFO0)
  {
    /* FIFO 0 assignation for the filter */
    CAN1->FFA1R &= ~(uint32_t)filter_number_bit_pos;
  }

  if (CAN_FilterInitStruct->CAN_FilterFIFOAssignment == CAN_Filter_FIFO1)
  {
    /* FIFO 1 assignation for the filter */
    CAN1->FFA1R |= (uint32_t)filter_number_bit_pos;
  }
  
  /* Filter activation */
  if (CAN_FilterInitStruct->CAN_FilterActivation == ENABLE)
  {
    CAN1->FA1R |= filter_number_bit_pos;
  }

  /* Leave the initialisation mode for the filter */
  CAN1->FMR &= ~FMR_FINIT;
}

/**
  * @brief  Fills each CAN_InitStruct member with its default value.
  * @param  CAN_InitStruct: pointer to a CAN_InitTypeDef structure which ill be initialized.
  * @retval 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;