CCS/TMS320F28379D: How to read the ID of a CAN message?

Hi Alessandro,

You can poll the corresponding interface register (IFx) CAN_IFxARB in the ISR to get the message ID.  If you are using the CAN examples from TI in C2000Ware, transmit objects typically use IF1 registers while receive objects use IF2, so you would need to read CAN_IF2ARB register.  The ID field is bits 28:0.  Double check on the specific code you are using for the actual object access/interface register being used to be sure.

Regards,

Joseph

Hi Joseph,
Thank you for you answer, however i still have a few issue.
To read the interface register im using

uint16_t msgID = HWREGH(CANB_BASE + CAN_IF2ARB_ID_M);

Hi Alessandro,

Sorry, forgot to add that you need to run function CAN_transferMessage() which is found in the can driverlib.  The message ID information is still in the message RAM.  In order to read the message ID from the CAN_IFxARB register, message RAM contents must be moved to the CAN_IFxARB register.

Regards,

Joseph

Hi Joseph

There is no such function as CAN_transferMessage() in the can.h driverlib.

This is the can.h file im referring to:

//###########################################################################
//
// FILE:   can.h
//
// TITLE:  C28x CAN driver.
//
//###########################################################################
// $TI Release: F2837xD Support Library v3.08.00.00 $
// $Release Date: Mon Dec 23 17:32:30 IST 2019 $
// $Copyright:
// Copyright (C) 2013-2019 Texas Instruments Incorporated - http://www.ti.com/
//
// Redistribution and use in source and binary forms, with or without 
// modification, are permitted provided that the following conditions 
// are met:
// 
//   Redistributions of source code must retain the above copyright 
//   notice, this list of conditions and the following disclaimer.
// 
//   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.
// 
//   Neither the name of Texas Instruments Incorporated 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 
// OWNER 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.
// $
//###########################################################################
#ifndef CAN_H
#define CAN_H


//*****************************************************************************
//
// If building with a C++ compiler, make all of the definitions in this header
// have a C binding.
//
//*****************************************************************************
#ifdef __cplusplus
extern "C"
{
#endif

#ifdef __TMS320C28XX__

//*****************************************************************************
//
//! \addtogroup can_api CAN
//! @{
//
//*****************************************************************************

#include <stdint.h>
#include <stdbool.h>
#include "inc/hw_memmap.h"
#include "inc/hw_types.h"
#include "inc/hw_can.h"
#include "debug.h"
#include "sysctl.h"

//
// The key value for RAM initialization
//
#define CAN_RAM_INIT_KEY           (0xAU)

//
// RAM Initialization Register Mask
//
#define CAN_RAM_INIT_MASK          (0x003FU)

//
// The Parity disable key value
//
#define CAN_INIT_PARITY_DISABLE    (0x1400U)

#ifndef DOXYGEN_PDF_IGNORE
//*****************************************************************************
//
// Miscellaneous defines for Message ID Types
//
//*****************************************************************************
//*****************************************************************************
//
// These are the flags used by the flags parameter when calling
// the CAN_setupMessageObject() function.
//
//*****************************************************************************

//! This indicates that transmit interrupts should be enabled, or are enabled.
#define CAN_MSG_OBJ_TX_INT_ENABLE          CAN_IF1MCTL_TXIE

//! This indicates that receive interrupts should be enabled, or are
//! enabled.
#define CAN_MSG_OBJ_RX_INT_ENABLE          CAN_IF1MCTL_RXIE

//! This indicates that a message object will use or is using filtering
//! based on the object's message identifier.
#define CAN_MSG_OBJ_USE_ID_FILTER          (0x00000001U)

//! This indicates that a message object will use or is using filtering
//! based on the direction of the transfer.
#define CAN_MSG_OBJ_USE_DIR_FILTER         CAN_IF1MSK_MDIR

//! This indicates that a message object will use or is using message
//! identifier filtering based on the extended identifier.
#define CAN_MSG_OBJ_USE_EXT_FILTER         CAN_IF1MSK_MXTD

//! This indicates that this message object is part of a FIFO structure and
//! not the final message object in a FIFO.
#define CAN_MSG_OBJ_FIFO                   (0x00000002U)

//! This indicates that a message object has no flags set.
#define CAN_MSG_OBJ_NO_FLAGS               (0x00000000U)

//*****************************************************************************
//
// These definitions are used to specify interrupt sources to
// CAN_enableInterrupt() and CAN_disableInterrupt().
//
//*****************************************************************************
//! This flag is used to allow a CAN controller to generate error
//! interrupts.
#define CAN_INT_ERROR              (0x00000008UL)

//! This flag is used to allow a CAN controller to generate status
//! interrupts.
#define CAN_INT_STATUS             (0x00000004UL)

//! This flag is used to allow a CAN controller to generate interrupts
//! on interrupt line 0
#define CAN_INT_IE0                (0x00000002UL)

//! This flag is used to allow a CAN controller to generate interrupts
//! on interrupt line 1
#define CAN_INT_IE1                (0x00020000UL)

//*****************************************************************************
//
// The following definitions contain all error or status indicators that can
// be returned when calling the CAN_getStatus() function.
//
//*****************************************************************************

//! CAN controller has detected a parity error.
#define CAN_STATUS_PERR                  (0x00000100U)

//! CAN controller has entered a Bus Off state.
#define CAN_STATUS_BUS_OFF               (0x00000080U)

//! CAN controller error level has reached warning level.
#define CAN_STATUS_EWARN                 (0x00000040U)

//! CAN controller error level has reached error passive level.
#define CAN_STATUS_EPASS                 (0x00000020U)

//! A message was received successfully since the last read of this status.
#define CAN_STATUS_RXOK                  (0x00000010U)

//! A message was transmitted successfully since the last read of this
//! status.
#define CAN_STATUS_TXOK                  (0x00000008U)

//! This is the mask for the last error code field.
#define CAN_STATUS_LEC_MSK               (0x00000007U)

//! There was no error.
#define CAN_STATUS_LEC_NONE              (0x00000000U)

//! A bit stuffing error has occurred.
#define CAN_STATUS_LEC_STUFF             (0x00000001U)

//! A formatting error has occurred.
#define CAN_STATUS_LEC_FORM              (0x00000002U)

//! An acknowledge error has occurred.
#define CAN_STATUS_LEC_ACK               (0x00000003U)

//! The bus remained a bit level of 1 for longer than is allowed.
#define CAN_STATUS_LEC_BIT1              (0x00000004U)

//! The bus remained a bit level of 0 for longer than is allowed.
#define CAN_STATUS_LEC_BIT0              (0x00000005U)

//! A CRC error has occurred.
#define CAN_STATUS_LEC_CRC               (0x00000006U)

//*****************************************************************************
//
// The following macros are added for the Global Interrupt EN/FLG/CLR
// register
//
//*****************************************************************************
//! CANINT0 global interrupt bit
#define CAN_GLOBAL_INT_CANINT0          (0x00000001U)

//! CANINT1 global interrupt bit
#define CAN_GLOBAL_INT_CANINT1          (0x00000002U)

//*****************************************************************************
//
// The following macros are added for accessing the interrupt register and
// the standard arbitration ID in the interface registers.
//
//*****************************************************************************
//! Status of INT0ID
#define CAN_INT_INT0ID_STATUS           (0x8000U)

//! IF1 Arbitration Standard ID Shift Offset
#define CAN_IF1ARB_STD_ID_S             (18U)

//! IF1 Arbitration Standard ID Mask
#define CAN_IF1ARB_STD_ID_M             (0x1FFC0000U)

//! IF2 Arbitration Standard ID Shift Offset
#define CAN_IF2ARB_STD_ID_S             (18U)

//! IF2 Arbitration Standard ID Mask
#define CAN_IF2ARB_STD_ID_M             (0x1FFC0000U)

#endif // DOXYGEN_PDF_IGNORE

//*****************************************************************************
//
//! This data type is used to decide between STD_ID or EXT_ID for a mailbox.
//! This is used when calling the CAN_setupMessageObject() function.
//
//*****************************************************************************
typedef enum
{
    //! Set the message ID frame to standard.
    CAN_MSG_FRAME_STD,

    //! Set the message ID frame to extended.
    CAN_MSG_FRAME_EXT
} CAN_MsgFrameType;

//*****************************************************************************
//
//! This definition is used to determine the type of message object that will
//! be set up via a call to the CAN_setupMessageObject() API.
//
//*****************************************************************************
typedef enum
{
    //! Transmit message object.
    CAN_MSG_OBJ_TYPE_TX,

    //! Transmit remote request message object
    CAN_MSG_OBJ_TYPE_TX_REMOTE,

    //! Receive message object.
    CAN_MSG_OBJ_TYPE_RX,

    //! Remote frame receive remote, with auto-transmit message object.
    CAN_MSG_OBJ_TYPE_RXTX_REMOTE
} CAN_MsgObjType;

//*****************************************************************************
//
//! This definition is used to determine the clock source that will
//! be set up via a call to the CAN_selectClockSource() API.
//
//*****************************************************************************
typedef enum
{
    //! Peripheral System Clock Source
    CAN_CLOCK_SOURCE_SYS    = 0x0,

    //! External Oscillator Clock Source
    CAN_CLOCK_SOURCE_XTAL   = 0x1,

    //! Auxiliary Clock Input Source
    CAN_CLOCK_SOURCE_AUX    = 0x2
} CAN_ClockSource;


//*****************************************************************************
//
// Prototypes for the APIs.
//
//*****************************************************************************
//*****************************************************************************
//
//! \internal
//!
//! Checks a CAN base address.
//!
//! \param base is the base address of the CAN controller.
//!
//! This function determines if a CAN controller base address is valid.
//!
//! \return Returns \b true if the base address is valid and \b false
//! otherwise.
//
//*****************************************************************************
#ifdef DEBUG
static inline bool
CAN_isBaseValid(uint32_t base)
{
    return((base == CANA_BASE) || (base == CANB_BASE));
}
#endif


//*****************************************************************************
//
//! \internal
//!
//! Copies data from the CAN Data registers to a buffer.
//!
//! \param data is a pointer to the data to be written out to the CAN
//! controller's data registers.
//! \param address is a uint32_t value for the first register of the
//! CAN controller's data registers.  For example, in order to use the IF1
//! register set on CAN controller 0, the value would be: \b CANA_BASE \b +
//! \b CAN_O_IF1DATA.
//! \param size is the number of bytes to copy into the CAN controller.
//!
//! This function takes the steps necessary to copy data from a contiguous
//! buffer in memory into the non-contiguous data registers used by the CAN
//! controller.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_writeDataReg(const uint16_t *const data, uint32_t address,
                 uint32_t size)
{
    uint32_t idx;
    uint32_t dataReg = address;

    //
    // Loop always copies 1 byte per iteration.
    //
    for(idx = 0U; idx < size; idx++)
    {
        //
        // Write out the data 8 bits at a time.
        //
        if(dataReg != 0U)
        {
            HWREGB(dataReg) = data[idx];

            dataReg++;
        }
    }
}

//*****************************************************************************
//
//! \internal
//!
//! Copies data from the CAN Data registers to a buffer.
//!
//! \param data is a pointer to the location to store the data read from the
//! CAN controller's data registers.
//! \param address is a uint32_t value for the first register of the
//! CAN controller's data registers.  For example, in order to use the IF1
//! register set on CAN controller 1, the value would be: \b CANA_BASE \b +
//! \b CAN_O_IF1DATA.
//! \param size is the number of bytes to copy from the CAN controller.
//!
//! This function takes the steps necessary to copy data to a contiguous buffer
//! in memory from the non-contiguous data registers used by the CAN
//! controller.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_readDataReg(uint16_t *data, const uint32_t address, uint32_t size)
{
    uint32_t idx;
    uint32_t dataReg = address;

    //
    // Loop always copies 1 byte per iteration.
    //
    for(idx = 0U; idx < size; idx++)
    {
        //
        // Read out the data
        //
        data[idx] = HWREGB(dataReg);

        dataReg++;
    }
}

//*****************************************************************************
//
//! Initializes the CAN controller's RAM.
//!
//! \param base is the base address of the CAN controller.
//!
//! Performs the initialization of the RAM used for the CAN message objects.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_initRAM(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    HWREGH(base + CAN_O_RAM_INIT) = CAN_RAM_INIT_CAN_RAM_INIT |
                                    CAN_RAM_INIT_KEY;

    while(!((HWREGH(base + CAN_O_RAM_INIT) & CAN_RAM_INIT_MASK) ==
            (CAN_RAM_INIT_RAM_INIT_DONE | CAN_RAM_INIT_KEY2 |
             CAN_RAM_INIT_KEY0)))
    {
        //
        // Wait until RAM Init is complete
        //
    }
}

//*****************************************************************************
//
//! Select CAN Clock Source
//!
//! \param base is the base address of the CAN controller.
//! \param source is the clock source to use for the CAN controller.
//!
//! This function selects the specified clock source for the CAN controller.
//!
//! The \e source parameter can be any one of the following:
//! - \b CAN_CLOCK_SOURCE_SYS  - Peripheral System Clock
//! - \b CAN_CLOCK_SOURCE_XTAL - External Oscillator
//! - \b CAN_CLOCK_SOURCE_AUX  - Auxiliary Clock Input from GPIO
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_selectClockSource(uint32_t base, CAN_ClockSource source)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Determine the CAN controller and set specified clock source
    //
    EALLOW;

    switch(base)
    {
        case CANA_BASE:
            HWREGH(CLKCFG_BASE + SYSCTL_O_CLKSRCCTL2) &=
                ~SYSCTL_CLKSRCCTL2_CANABCLKSEL_M;

            HWREGH(CLKCFG_BASE + SYSCTL_O_CLKSRCCTL2) |= ((uint16_t)source <<
                SYSCTL_CLKSRCCTL2_CANABCLKSEL_S);
            break;

        case CANB_BASE:
            HWREGH(CLKCFG_BASE + SYSCTL_O_CLKSRCCTL2) &=
                ~SYSCTL_CLKSRCCTL2_CANBBCLKSEL_M;

            HWREGH(CLKCFG_BASE + SYSCTL_O_CLKSRCCTL2) |= ((uint16_t)source <<
                SYSCTL_CLKSRCCTL2_CANBBCLKSEL_S);
            break;

        default:

            //
            // Do nothing. Not a valid mode value.
            //
            break;
    }

    EDIS;
}

//*****************************************************************************
//
//! Starts the CAN Module's Operations
//!
//! \param base is the base address of the CAN controller.
//!
//! This function starts the CAN module's operations after initialization,
//! which includes the CAN protocol controller state machine of the CAN core
//! and the message handler state machine to begin controlling the CAN's
//! internal data flow.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_startModule(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Clear Init and CCE bits
    //
    HWREGH(base + CAN_O_CTL) &= ~(CAN_CTL_INIT | CAN_CTL_CCE);
}

//*****************************************************************************
//
//! Enables the CAN controller.
//!
//! \param base is the base address of the CAN controller to enable.
//!
//! Enables the CAN controller for message processing.  Once enabled, the
//! controller will automatically transmit any pending frames, and process any
//! received frames.  The controller can be stopped by calling
//! CAN_disableController().
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_enableController(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Clear the init bit in the control register.
    //
    HWREGH(base + CAN_O_CTL) &= ~CAN_CTL_INIT;
}

//*****************************************************************************
//
//! Disables the CAN controller.
//!
//! \param base is the base address of the CAN controller to disable.
//!
//! Disables the CAN controller for message processing.  When disabled, the
//! controller will no longer automatically process data on the CAN bus.  The
//! controller can be restarted by calling CAN_enableController().  The state
//! of the CAN controller and the message objects in the controller are left as
//! they were before this call was made.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_disableController(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Set the init bit in the control register.
    //
    HWREGH(base + CAN_O_CTL) |= CAN_CTL_INIT;
}

//*****************************************************************************
//
//! Enables the test modes of the CAN controller.
//!
//! \param base is the base address of the CAN controller.
//! \param mode are the the test modes to enable.
//!
//! Enables test modes within the controller.  The following valid options for
//! \e mode can be OR'ed together:
//! - \b CAN_TEST_SILENT - Silent Mode
//! - \b CAN_TEST_LBACK  - Loopback Mode
//! - \b CAN_TEST_EXL    - External Loopback Mode
//!
//! \note Loopback mode and external loopback mode \b can \b not be
//! enabled at the same time.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_enableTestMode(uint32_t base, uint16_t mode)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));
    ASSERT((mode & (CAN_TEST_LBACK | CAN_TEST_EXL)) !=
           (CAN_TEST_LBACK | CAN_TEST_EXL));

    //
    // Clear the bits in the test register.
    //
    HWREGH(base + CAN_O_TEST) &= ~((uint16_t)CAN_TEST_SILENT |
                                   (uint16_t)CAN_TEST_LBACK |
                                   (uint16_t)CAN_TEST_EXL);

    //
    // Enable test mode and set the bits in the test register.
    //
    HWREGH(base + CAN_O_CTL) |= CAN_CTL_TEST;
    HWREGH(base + CAN_O_TEST) |= mode;
}

//*****************************************************************************
//
//! Disables the test modes of the CAN controller.
//!
//! \param base is the base address of the CAN controller.
//!
//! Disables test modes within the controller and clears the test bits.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_disableTestMode(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Clear the bits in the test register.
    //
    HWREGH(base + CAN_O_TEST) &= ~((uint16_t)CAN_TEST_SILENT |
                                   (uint16_t)CAN_TEST_LBACK |
                                   (uint16_t)CAN_TEST_EXL);

    //
    // Clear the test mode enable bit
    //
    HWREGH(base + CAN_O_CTL) &= ~CAN_CTL_TEST;
}

//*****************************************************************************
//
//! Get the current settings for the CAN controller bit timing.
//!
//! \param base is the base address of the CAN controller.
//!
//! This function reads the current configuration of the CAN controller bit
//! clock timing.
//!
//! \return Returns the value of the bit timing register.
//
//*****************************************************************************
static inline uint32_t
CAN_getBitTiming(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Read and return BTR register
    //
    return(HWREG_BP(base + CAN_O_BTR));
}

//*****************************************************************************
//
//! Enables direct access to the RAM.
//!
//! \param base is the base address of the CAN controller.
//!
//! Enables direct access to the RAM while in Test mode.
//!
//! \note Test Mode must first be enabled to use this function.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_enableMemoryAccessMode(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Set the RAM direct access bit
    //
    HWREGH(base + CAN_O_TEST) |= CAN_TEST_RDA;
}

//*****************************************************************************
//
//! Disables direct access to the RAM.
//!
//! \param base is the base address of the CAN controller.
//!
//! Disables direct access to the RAM while in Test mode.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_disableMemoryAccessMode(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Clear the RAM direct access bit
    //
    HWREGH(base + CAN_O_TEST) &= ~CAN_TEST_RDA;
}

//*****************************************************************************
//
//! Sets the interruption debug mode of the CAN controller.
//!
//! \param base is the base address of the CAN controller.
//! \param enable is a flag to enable or disable the interruption debug mode.
//!
//! This function sets the interruption debug mode of the CAN controller. When
//! the \e enable parameter is \b true, CAN will be configured to interrupt any
//! transmission or reception and enter debug mode immediately after it is
//! requested. When \b false, CAN will wait for a started transmission or
//! reception to be completed before entering debug mode.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_setInterruptionDebugMode(uint32_t base, bool enable)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    if(enable)
    {
        //
        // Enable interrupt debug support
        //
        HWREGH(base + CAN_O_CTL) |= CAN_CTL_IDS;
    }
    else
    {
        //
        // Disable interrupt debug support
        //
        HWREGH(base + CAN_O_CTL) &= ~CAN_CTL_IDS;
    }
}


//*****************************************************************************
//
//! Disables Auto-Bus-On.
//!
//! \param base is the base address of the CAN controller.
//!
//! Disables the Auto-Bus-On feature of the CAN controller.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_disableAutoBusOn(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Clear the ABO bit in the control register.
    //
    HWREGH(base + CAN_O_CTL) &= ~CAN_CTL_ABO;
}

//*****************************************************************************
//
//! Enables Auto-Bus-On.
//!
//! \param base is the base address of the CAN controller.
//!
//! Enables the Auto-Bus-On feature of the CAN controller.  Be sure to also
//! configure the Auto-Bus-On time using the CAN_setAutoBusOnTime function.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_enableAutoBusOn(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Set the ABO bit in the control register.
    //
    HWREGH(base + CAN_O_CTL) |= CAN_CTL_ABO;
}

//*****************************************************************************
//
//! Sets the time before a Bus-Off recovery sequence is started.
//!
//! \param base is the base address of the CAN controller.
//! \param time is number of clock cycles before a Bus-Off recovery sequence
//!        is started.
//!
//! This function sets the number of clock cycles before a Bus-Off recovery
//! sequence is started by clearing the Init bit.
//!
//! \note To enable this functionality, use CAN_enableAutoBusOn().
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_setAutoBusOnTime(uint32_t base, uint32_t time)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Set bus-off timer value
    //
    HWREG_BP(base + CAN_O_ABOTR) = time;
}

//*****************************************************************************
//
//! Enables individual CAN controller interrupt sources.
//!
//! \param base is the base address of the CAN controller.
//! \param intFlags is the bit mask of the interrupt sources to be enabled.
//!
//! Enables specific interrupt sources of the CAN controller.  Only enabled
//! sources will cause a processor interrupt.
//!
//! The \e intFlags parameter is the logical OR of any of the following:
//! - \b CAN_INT_ERROR - a controller error condition has occurred
//! - \b CAN_INT_STATUS - a message transfer has completed, or a bus error has
//! been detected
//! - \b CAN_INT_IE0 - allow CAN controller to generate interrupts on interrupt
//! line 0
//! - \b CAN_INT_IE1 - allow CAN controller to generate interrupts on interrupt
//! line 1
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_enableInterrupt(uint32_t base, uint32_t intFlags)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));
    ASSERT((intFlags & ~(CAN_INT_ERROR | CAN_INT_STATUS | CAN_INT_IE0 |
                         CAN_INT_IE1)) == 0U);

    //
    // Enable the specified interrupts.
    //
    HWREG_BP(base + CAN_O_CTL) |= intFlags;
}

//*****************************************************************************
//
//! Disables individual CAN controller interrupt sources.
//!
//! \param base is the base address of the CAN controller.
//! \param intFlags is the bit mask of the interrupt sources to be disabled.
//!
//! Disables the specified CAN controller interrupt sources.  Only enabled
//! interrupt sources can cause a processor interrupt.
//!
//! The \e intFlags parameter has the same definition as in the
//! CAN_enableInterrupt() function.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_disableInterrupt(uint32_t base, uint32_t intFlags)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));
    ASSERT((intFlags & ~(CAN_INT_ERROR | CAN_INT_STATUS | CAN_INT_IE0 |
                         CAN_INT_IE1)) == 0U);

    //
    // Disable the specified interrupts.
    //
    HWREG_BP(base + CAN_O_CTL) &= ~(intFlags);
}

//*****************************************************************************
//
//! Get the CAN controller Interrupt Line set for each mailbox
//!
//! \param base is the base address of the CAN controller.
//!
//! Gets which interrupt line each message object should assert when an
//! interrupt occurs. Bit 0 corresponds to message object 32 and then bits
//! 1 to 31 correspond to message object 1 through 31 respectively. Bits that
//! are asserted indicate the message object should generate an interrupt on
//! interrupt line 1, while bits that are not asserted indicate the message
//! object should generate an interrupt on line 0.
//!
//! \return Returns the value of the interrupt muxing register.
//
//*****************************************************************************
static inline uint32_t
CAN_getInterruptMux(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Get the interrupt muxing for the CAN peripheral
    //
    return(HWREG_BP(base + CAN_O_IP_MUX21));
}

//*****************************************************************************
//
//! Set the CAN controller Interrupt Line for each mailbox
//!
//! \param base is the base address of the CAN controller.
//! \param mux bit packed representation of which message objects should
//!        generate an interrupt on a given interrupt line.
//!
//! Selects which interrupt line each message object should assert when an
//! interrupt occurs. Bit 0 corresponds to message object 32 and then bits
//! 1 to 31 correspond to message object 1 through 31 respectively. Bits that
//! are asserted indicate the message object should generate an interrupt on
//! interrupt line 1, while bits that are not asserted indicate the message
//! object should generate an interrupt on line 0.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_setInterruptMux(uint32_t base, uint32_t mux)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Set the interrupt muxing for the CAN peripheral
    //
    HWREG_BP(base + CAN_O_IP_MUX21) = mux;
}

//*****************************************************************************
//
//! Enables the CAN controller automatic retransmission behavior.
//!
//! \param base is the base address of the CAN controller.
//!
//! Enables the automatic retransmission of messages with detected errors.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_enableRetry(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Clearing the DAR bit tells the controller to not disable the
    // auto-retry of messages which were not transmitted or received
    // correctly.
    //
    HWREGH(base + CAN_O_CTL) &= ~CAN_CTL_DAR;
}

//*****************************************************************************
//
//! Disables the CAN controller automatic retransmission behavior.
//!
//! \param base is the base address of the CAN controller.
//!
//! Disables the automatic retransmission of messages with detected errors.
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_disableRetry(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Setting the DAR bit tells the controller to disable the auto-retry
    // of messages which were not transmitted or received correctly.
    //
    HWREGH(base + CAN_O_CTL) |= CAN_CTL_DAR;
}

//*****************************************************************************
//
//! Returns the current setting for automatic retransmission.
//!
//! \param base is the base address of the CAN controller.
//!
//! Reads the current setting for the automatic retransmission in the CAN
//! controller and returns it to the caller.
//!
//! \return Returns \b true if automatic retransmission is enabled, \b false
//! otherwise.
//
//*****************************************************************************
static inline bool
CAN_isRetryEnabled(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Read the disable automatic retry setting from the CAN controller.
    //
    return((bool)((HWREGH(base + CAN_O_CTL) & CAN_CTL_DAR) != CAN_CTL_DAR));
}

//*****************************************************************************
//
//! Reads the CAN controller error counter register.
//!
//! \param base is the base address of the CAN controller.
//! \param rxCount is a pointer to storage for the receive error counter.
//! \param txCount is a pointer to storage for the transmit error counter.
//!
//! Reads the error counter register and returns the transmit and receive error
//! counts to the caller along with a flag indicating if the controller receive
//! counter has reached the error passive limit.  The values of the receive and
//! transmit error counters are returned through the pointers provided as
//! parameters.
//!
//! After this call, \e rxCount will hold the current receive error count
//! and \e txCount will hold the current transmit error count.
//!
//! \return Returns \b true if the receive error count has reached the error
//! passive limit, and \b false if the error count is below the error passive
//! limit.
//
//*****************************************************************************
static inline bool
CAN_getErrorCount(uint32_t base, uint32_t *rxCount, uint32_t *txCount)
{
    uint32_t canError = 0U;

    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Read the current count of transmit/receive errors.
    //
    canError = HWREG_BP(base + CAN_O_ERRC);

    //
    // Extract the error numbers from the register value.
    //
    *rxCount = (canError & CAN_ERRC_REC_M) >> CAN_ERRC_REC_S;
    *txCount = (canError & CAN_ERRC_TEC_M) >> CAN_ERRC_TEC_S;

    return((bool)((canError & CAN_ERRC_RP) != 0U));
}

//*****************************************************************************
//
//! Reads the CAN controller error and status register.
//!
//! \param base is the base address of the CAN controller.
//!
//! Reads the error and status register of the CAN controller.
//!
//! \return Returns the value of the register.
//
//*****************************************************************************
static inline uint16_t
CAN_getStatus(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Return error and status register value
    //
    return(HWREGH(base + CAN_O_ES));
}

//*****************************************************************************
//
//! Reads the CAN controller TX request register.
//!
//! \param base is the base address of the CAN controller.
//!
//! Reads the TX request register of the CAN controller.
//!
//! \return Returns the value of the register.
//
//*****************************************************************************
static inline uint32_t
CAN_getTxRequests(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Return Tx requests register value
    //
    return(HWREG_BP(base + CAN_O_TXRQ_21));
}

//*****************************************************************************
//
//! Reads the CAN controller new data status register.
//!
//! \param base is the base address of the CAN controller.
//!
//! Reads the new data status register of the CAN controller for all message
//! objects.
//!
//! \return Returns the value of the register.
//
//*****************************************************************************
static inline uint32_t
CAN_getNewDataFlags(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Return new data register value
    //
    return(HWREG_BP(base + CAN_O_NDAT_21));
}

//*****************************************************************************
//
//! Reads the CAN controller valid message object register.
//!
//! \param base is the base address of the CAN controller.
//!
//! Reads the valid message object register of the CAN controller.
//!
//! \return Returns the value of the register.
//
//*****************************************************************************
static inline uint32_t
CAN_getValidMessageObjects(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Return the valid message register value
    //
    return(HWREG_BP(base + CAN_O_MVAL_21));
}

//*****************************************************************************
//
//! Get the CAN controller interrupt cause.
//!
//! \param base is the base address of the CAN controller.
//!
//! This function returns the value of the interrupt register that indicates
//! the cause of the interrupt.
//!
//! \return Returns the value of the interrupt register.
//
//*****************************************************************************
static inline uint32_t
CAN_getInterruptCause(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Read interrupt identifier status
    //
    return(HWREG_BP(base + CAN_O_INT));
}

//*****************************************************************************
//
//! Get the CAN controller pending interrupt message source.
//!
//! \param base is the base address of the CAN controller.
//!
//! Returns the value of the pending interrupts register that indicates
//! which messages are the source of pending interrupts.
//!
//! \return Returns the value of the pending interrupts register.
//
//*****************************************************************************
static inline uint32_t
CAN_getInterruptMessageSource(uint32_t base)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));

    //
    // Read message object interrupt status
    //
    return(HWREG_BP(base + CAN_O_IPEN_21));
}

//*****************************************************************************
//
//! CAN Global interrupt Enable function.
//!
//! \param base is the base address of the CAN controller.
//! \param intFlags is the bit mask of the interrupt sources to be enabled.
//!
//! Enables specific CAN interrupt in the global interrupt enable register
//!
//! The \e intFlags parameter is the logical OR of any of the following:
//! - \b CAN_GLOBAL_INT_CANINT0  - Global Interrupt Enable bit for CAN INT0
//! - \b CAN_GLOBAL_INT_CANINT1  - Global Interrupt Enable bit for CAN INT1
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_enableGlobalInterrupt(uint32_t base, uint16_t intFlags)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));
    ASSERT((intFlags & ~(CAN_GLOBAL_INT_CANINT0 |
                         CAN_GLOBAL_INT_CANINT1)) == 0U);

    //
    // Enable the requested interrupts
    //
    HWREGH(base + CAN_O_GLB_INT_EN) |= intFlags;
}

//*****************************************************************************
//
//! CAN Global interrupt Disable function.
//!
//! \param base is the base address of the CAN controller.
//! \param intFlags is the bit mask of the interrupt sources to be disabled.
//!
//! Disables the specific CAN interrupt in the global interrupt enable register
//!
//! The \e intFlags parameter is the logical OR of any of the following:
//! - \b CAN_GLOBAL_INT_CANINT0 - Global Interrupt bit for CAN INT0
//! - \b CAN_GLOBAL_INT_CANINT1 - Global Interrupt bit for CAN INT1
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_disableGlobalInterrupt(uint32_t base, uint16_t intFlags)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));
    ASSERT((intFlags & ~(CAN_GLOBAL_INT_CANINT0 |
                         CAN_GLOBAL_INT_CANINT1)) == 0U);

    //
    // Disable the requested interrupts
    //
    HWREGH(base + CAN_O_GLB_INT_EN) &= ~intFlags;
}

//*****************************************************************************
//
//! CAN Global interrupt Clear function.
//!
//! \param base is the base address of the CAN controller.
//! \param intFlags is the bit mask of the interrupt sources to be cleared.
//!
//! Clear the specific CAN interrupt bit in the global interrupt flag register.
//!
//! The \e intFlags parameter is the logical OR of any of the following:
//! - \b CAN_GLOBAL_INT_CANINT0 - Global Interrupt bit for CAN INT0
//! - \b CAN_GLOBAL_INT_CANINT1 - Global Interrupt bit for CAN INT1
//!
//! \return None.
//
//*****************************************************************************
static inline void
CAN_clearGlobalInterruptStatus(uint32_t base, uint16_t intFlags)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));
    ASSERT((intFlags & ~(CAN_GLOBAL_INT_CANINT0 |
                         CAN_GLOBAL_INT_CANINT1)) == 0U);

    //
    // Clear the requested interrupts
    //
    HWREGH(base + CAN_O_GLB_INT_CLR) |= intFlags;
}

//*****************************************************************************
//
//! Get the CAN Global Interrupt status.
//!
//! \param base is the base address of the CAN controller.
//! \param intFlags is the bit mask of the interrupt sources to be enabled.
//!
//! Check if any interrupt bit is set in the global interrupt flag register.
//!
//! The \e intFlags parameter is the logical OR of any of the following:
//! - \b CAN_GLOBAL_INT_CANINT0 - Global Interrupt bit for CAN INT0
//! - \b CAN_GLOBAL_INT_CANINT1 - Global Interrupt bit for CAN INT1
//!
//! \return True if any of the requested interrupt bits are set. False, if
//! none of the requested bits are set.
//
//*****************************************************************************
static inline bool
CAN_getGlobalInterruptStatus(uint32_t base, uint16_t intFlags)
{
    //
    // Check the arguments.
    //
    ASSERT(CAN_isBaseValid(base));
    ASSERT((intFlags & ~(CAN_GLOBAL_INT_CANINT0 |
                         CAN_GLOBAL_INT_CANINT1)) == 0U);

    //
    // Read and return the global interrupt flag register
    //
    return((bool)((HWREGH(base + CAN_O_GLB_INT_FLG) & intFlags) != 0U));
}

//*****************************************************************************
//
//! Initializes the CAN controller
//!
//! \param base is the base address of the CAN controller.
//!
//! This function initializes the message RAM, which also clears all the
//! message objects, and places the CAN controller in an init state. Write
//! access to the configuration registers is available as a result, allowing
//! the bit timing and message objects to be setup.
//!
//! \note To exit the initialization mode and start the CAN module, use the
//! CAN_startModule() function.
//!
//! \return None.
//
//*****************************************************************************
extern void
CAN_initModule(uint32_t base);

//*****************************************************************************
//
//! Sets the CAN Bit Timing based on requested Bit Rate.
//!
//! \param base is the base address of the CAN controller.
//! \param clock is the CAN module clock frequency before the bit rate
//!        prescaler (Hertz)
//! \param bitRate is the desired bit rate (bits/sec)
//! \param bitTime is the number of time quanta per bit required for desired
//!        bit time (Tq) and must be in the range from 8 to 25
//!
//! This function sets the CAN bit timing values for the bit rate passed in the
//! \e bitRate and \e bitTime parameters based on the \e clock parameter.  The
//! CAN bit clock is calculated to be an average timing value that should work
//! for most systems.  If tighter timing requirements are needed, then the
//! CAN_setBitTiming() function is available for full customization of all of
//! the CAN bit timing values.
//!
//! \note The CANBTR register values calculated by the function CAN_setBitRate
//!       may not be suitable for your network parameters. If this is the case
//!       and you have computed the correct values for your network, you could
//!       directly write those parameters in CANBTR register using the
//!       function CAN_setBitTiming.
//!
//! \return None.
//
//*****************************************************************************
extern void
CAN_setBitRate(uint32_t base, uint32_t clock, uint32_t bitRate,
               uint16_t bitTime);

//*****************************************************************************
//
//! Manually set the CAN controller bit timing.
//!
//! \param base is the base address of the CAN controller.
//! \param prescaler is the baud rate prescaler
//! \param prescalerExtension is the baud rate prescaler extension
//! \param tSeg1 is the time segment 1
//! \param tSeg2 is the time segment 2
//! \param sjw is the synchronization jump width
//!
//! This function sets the various timing parameters for the CAN bus bit
//! timing: baud rate prescaler, prescaler extension, time segment 1,
//! time segment 2, and the Synchronization Jump Width.
//!
//! \return None.
//
//*****************************************************************************
extern void
CAN_setBitTiming(uint32_t base, uint16_t prescaler,
                 uint16_t prescalerExtension, uint16_t tSeg1, uint16_t tSeg2,
                 uint16_t sjw);


//*****************************************************************************
//
//! Clears a CAN interrupt source.
//!
//! \param base is the base address of the CAN controller.
//! \param intClr is a value indicating which interrupt source to clear.
//!
//! This function can be used to clear a specific interrupt source.  The
//! \e intClr parameter should be either a number from 1 to 32 to clear a
//! specific message object interrupt or can be the following:
//! - \b CAN_INT_INT0ID_STATUS - Clears a status interrupt.
//!
//! It is not necessary to use this function to clear an interrupt.  This
//! should only be used if the application wants to clear an interrupt source
//! without taking the normal interrupt action.
//!
//! \return None.
//
//*****************************************************************************
extern void
CAN_clearInterruptStatus(uint32_t base, uint32_t intClr);

//*****************************************************************************
//
//! Setup a Message Object
//!
//! \param base is the base address of the CAN controller.
//! \param objID is the message object number to configure (1-32).
//! \param msgID is the CAN message identifier used for the 11 or 29 bit
//!        identifiers
//! \param frame is the CAN ID frame type
//! \param msgType is the message object type
//! \param msgIDMask is the CAN message identifier mask used when identifier
//!        filtering is enabled
//! \param flags is the various flags and settings to be set for the message
//!        object
//! \param msgLen is the number of bytes of data in the message object (0-8)
//!
//! This function sets the various values required for a message object.
//!
//! The \e frame parameter can be one of the following values:
//! - \b CAN_MSG_FRAME_STD - Standard 11 bit identifier
//! - \b CAN_MSG_FRAME_EXT - Extended 29 bit identifier
//!
//! The \e msgType parameter can be one of the following values:
//! - \b CAN_MSG_OBJ_TYPE_TX          - Transmit Message
//! - \b CAN_MSG_OBJ_TYPE_TX_REMOTE   - Transmit Remote Message
//! - \b CAN_MSG_OBJ_TYPE_RX          - Receive Message
//! - \b CAN_MSG_OBJ_TYPE_RXTX_REMOTE - Receive Remote message with
//!                                     auto-transmit
//!
//! The \e flags parameter can be set as \b CAN_MSG_OBJ_NO_FLAGS if no flags
//! are required or the parameter can be a logical OR of any of the following
//! values:
//! - \b CAN_MSG_OBJ_TX_INT_ENABLE    - Enable Transmit Interrupts
//! - \b CAN_MSG_OBJ_RX_INT_ENABLE    - Enable Receive Interrupts
//! - \b CAN_MSG_OBJ_USE_ID_FILTER    - Use filtering based on the Message ID
//! - \b CAN_MSG_OBJ_USE_EXT_FILTER   - Use filtering based on the Extended
//!                                     Message ID
//! - \b CAN_MSG_OBJ_USE_DIR_FILTER   - Use filtering based on the direction of
//!                                     the transfer
//! - \b CAN_MSG_OBJ_FIFO             - Message object is part of a FIFO
//!                                     structure and isn't the final message
//!                                     object in FIFO
//!
//! If filtering is based on message identifier, the value
//! \b CAN_MSG_OBJ_USE_ID_FILTER has to be logically ORed with the \e flag
//! parameter and \b CAN_MSG_OBJ_USE_EXT_FILTER also has to be ORed for
//! message identifier filtering to be based on the extended identifier.
//!
//! \note The \b msgLen Parameter for the Receive Message Object is a "don't
//!       care" but its value should be between 0-8 due to the assert.
//!
//! \return None.
//
//*****************************************************************************
extern void
CAN_setupMessageObject(uint32_t base, uint32_t objID, uint32_t msgID,
                       CAN_MsgFrameType frame, CAN_MsgObjType msgType,
                       uint32_t msgIDMask, uint32_t flags, uint16_t msgLen);

//*****************************************************************************
//
//! Sends a Message Object
//!
//! \param base is the base address of the CAN controller.
//! \param objID is the object number to configure (1-32).
//! \param msgLen is the number of bytes of data in the message object (0-8)
//! \param msgData is a pointer to the message object's data
//!
//! This function is used to transmit a message object and the message data,
//! if applicable.
//!
//! \note The message object requested by the \e objID must first be setup
//! using the CAN_setupMessageObject() function.
//!
//! \return None.
//
//*****************************************************************************
extern void
CAN_sendMessage(uint32_t base, uint32_t objID, uint16_t msgLen,
                const uint16_t *msgData);

//*****************************************************************************
//
//! Reads the data in a Message Object
//!
//! \param base is the base address of the CAN controller.
//! \param objID is the object number to read (1-32).
//! \param msgData is a pointer to the array to store the message data
//!
//! This function is used to read the data contents of the specified message
//! object in the CAN controller. The data returned is stored in the
//! \e msgData parameter.
//!
//! \note
//! -# The message object requested by the \e objID must first be setup
//! using the CAN_setupMessageObject() function.
//! -# If the DLC of the received message is larger than the \e msgData
//! buffer provided, then it is possible for a buffer overflow to occur.
//!
//! \return Returns \b true if new data was retrieved, else returns
//! \b false to indicate no new data was retrieved.
//
//*****************************************************************************
extern bool
CAN_readMessage(uint32_t base, uint32_t objID,
                uint16_t *msgData);


//*****************************************************************************
//
//! Transfers a CAN message between the IF registers and Message RAM.
//!
//! \param base is the base address of the CAN controller.
//! \param interface is the interface to use for the transfer. Valid value are
//!        1 or 2.
//! \param objID is the object number to transfer (1-32).
//! \param direction is the direction of data transfer. False is Message RAM 
//!        to IF, True is IF to Message RAM.
//!
//! This function transfers the contents of the interface registers to message
//! RAM or vice versa depending on the value passed to direction.
//!
//! \return None.
//
//*****************************************************************************
extern void
CAN_transferMessage(uint32_t base, uint16_t interface, uint32_t objID,
                    bool direction);

//*****************************************************************************
//
//! Clears a message object so that it is no longer used.
//!
//! \param base is the base address of the CAN controller.
//! \param objID is the message object number to disable (1-32).
//!
//! This function frees the specified message object from use.  Once a message
//! object has been cleared, it will no longer automatically send or
//! receive messages, or generate interrupts.
//!
//! \return None.
//
//*****************************************************************************
extern void
CAN_clearMessage(uint32_t base, uint32_t objID);

//*****************************************************************************
//
// Close the Doxygen group.
//! @}
//
//*****************************************************************************

#endif // #ifdef __TMS320C28XX__

//*****************************************************************************
//
// Mark the end of the C bindings section for C++ compilers.
//
//*****************************************************************************
#ifdef __cplusplus
}
#endif

#endif //  CAN_H

I couldnt find a similar function to the one you are referring to, could you help me?

Hi Alessandro,

      What is in can.h is the external reference:

Hi Joseph
Thankyou for you answer, i found out that the version of C2000 ware i was using was no up to date, therefore the missing function.
However, i still cant figure out what am i doing wrong as im still unable to read the message ID from the CAN_IF2ARB register.

This is the message object:

    CAN_setupMessageObject(CANB_BASE, OBJ_ID_FROM_AMK, 0x283,           
                           CAN_MSG_FRAME_STD, CAN_MSG_OBJ_TYPE_RX, 0,
                           CAN_MSG_OBJ_RX_INT_ENABLE, MSG_DATA_LENGTH);

this is what happen in the isr that handle the message reception:

            CAN_readMessage(CANB_BASE, OBJ_ID_FROM_AMK, AMK_Values1_temp);
            id = getMessageID();

and this is the function getMessageID() :

uint32_t getMessageID()
{
    uint32_t msgID = 0;
    uint32_t elevenBitID = 2047;

    CAN_transferMessage(CANB_BASE, 2, OBJ_ID_FROM_AMK, false);


    msgID = HWREGH(CANB_BASE + CAN_O_IF2ARB);
    msgID = msgID & elevenBitID;
    return msgID;
}

Since im using the 11-bit identifier by doing msgID = msgID & elevenBitID i only consider the eleven bit of the register.

By running the program the message reception works fine but the msgID is 0.

Any help is appreciated.

Hi Alessandro,

It is probably best then that you download the latest C2000Ware to get the API for transferring the message ram contents to the CAN IFx registers, otherwise you need to write your own function to configure the transfer direction and data in CAN_IF2CMD register (since it seems like you are using IF2 in your application).  Details of the CAN_IF2CMD register fields are available the F2837xD TRM, which you can download online.

Regards,

Joseph