DCA1000EVM: Bus error (core dumped) using CLI Application to capture raw data on Linux

Hello,

yes, I tried it on an x86 based system and it worked fine. There are no binaries included in the package.

In the meantime, I was able to solve the problem myself. I will briefly explain what I did to get it running. Maybe it makes sense to include a similar fix in a future update.

The SIGBUS Error is caused by an unaligned memory access in connection with pthread functions. I don't know exacly why the memory must be aligned for these function, because the arm64v8 in general supports unaligned memory access. Perhaps it is caused by deeper machine commands of this library.

In several header files there is a statement: (for example rf_api.h)

/** To avoid structure padding                                               */
#pragma pack (1)

Caused by this statement, there is no memory alignment to 64bit of the architecture. This indirectly triggers the problem but reduces the memory used and maybe some other higher purpose.

No matter, if you want to keep these statements, it needs to be fixed at the two locations, where the error occurs:

In osal.h the struct OSAL_SIGNAL_HANDLE_TYPE contains a pthread_cond_t(48B), pthread_mutex_t(48B) and a bool(1B) variable. In sum this struct takes 97Bytes. This need to be aligned to 104 Bytes, for example with this modification: alignas(8)

/** Structure definition for event handle (Linux)       */
typedef struct alignas(8)
{
    /** Condition variable handle  */
    OSAL_CONDN_HANDLE_TYPE condnVar;

    /** Mutex variable handle      */
    OSAL_MUTEX_HANDLE_TYPE mutexVar;

    /** Signalled state flag       */

    bool bSignalled;
}OSAL_SIGNAL_HANDLE_TYPE;

In recorddatarecv.h is the class with a lot of variables. Two of them are the event structures of the previously changed struct. I assume the event structs are already aligned to 104B. So these structs start at an offset of 1299B and 1403B. The offset need to be aligned. The easiest way is to simply move the event structs to the beginning of the memory. By that they start at an offset of 0B and 104B:

(Left - original   Right - modification)

class cUdpDataReceiver

{

	/** Data type index										*/

    UINT8 u8DataTypeId;



    /** Record data file pointer                            */

    FILE *pRecordDataFile;



    /** Record data file path                               */

    SINT8 strRecordFilePath[MAX_NAME_LEN * 2];



    /** Record data file name                               */

    SINT8 strFileName1 [MAX_NAME_LEN * 3];



    /** Socket state                */

    bool bSocketState;



    /** Thread state                */

    bool bThreadState;



    /** First packet state          */

    bool bFirstPktSeqSet;



    /** File Data count             */

    UINT32 u32DataCount;



    /** File count                  */

    UINT32 u32DataFileCount;



	/** File writing - Loop index	*/

    UINT32 u32ByteIndex;



    #ifndef POST_PROCESSING



    /** File write completion wait event                    */

    OSAL_SIGNAL_HANDLE_TYPE sgnFileWriteCompletionWaitEvent;



    /** File write init wait event                          */

    OSAL_SIGNAL_HANDLE_TYPE sgnFileWriteInitWaitEvent;



    /** Buffer 1 empty flag                                 */

    bool bBuf1Empty;
    
...

class cUdpDataReceiver

{   

    #ifndef POST_PROCESSING



    /** File write completion wait event                    */

    OSAL_SIGNAL_HANDLE_TYPE sgnFileWriteCompletionWaitEvent;



    /** File write init wait event                          */

    OSAL_SIGNAL_HANDLE_TYPE sgnFileWriteInitWaitEvent;



    #endif



	/** Data type index										*/

    UINT8 u8DataTypeId;



    /** Record data file pointer                            */

    FILE *pRecordDataFile;



    /** Record data file path                               */

    SINT8 strRecordFilePath[MAX_NAME_LEN * 2];



    /** Record data file name                               */

    SINT8 strFileName1 [MAX_NAME_LEN * 3];



    /** Socket state                */

    bool bSocketState;



    /** Thread state                */

    bool bThreadState;



    /** First packet state          */

    bool bFirstPktSeqSet;



    /** File Data count             */

    UINT32 u32DataCount;



    /** File count                  */

    UINT32 u32DataFileCount;



	/** File writing - Loop index	*/

    UINT32 u32ByteIndex;



    #ifndef POST_PROCESSING



    /** Buffer 1 empty flag                                 */

    bool bBuf1Empty;
    
...

With these modifications it works for me.

I hope with this post I save other people a lot of work to get the CLI tool running on arm64 based systems.

Best regards

Hans-Peter