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Problem about MPC5744P FlexCAN on S32DS

Question asked by 鑫 犹 on Oct 29, 2018
Latest reply on Oct 30, 2018 by 鑫 犹


I have a problem when I build my project using S32DS.I want to use the FlexCAN module to receive multiple data and process the messages in the interrupt,but I'm failed.The ProcessorExpert only provide the following function prototypes which seems to be useful.

void FLEXCAN_DRV_InstallEventCallback(uint8_t instance,
flexcan_callback_t callback,
void *callbackParam);

And I use it in my code,here like this:

static void ReceiveCANData(uint32_t mailbox, uint32_t messageId,
flexcan_msgbuff_t * data_buf_struct, uint32_t len)
/*configure the data Info*/
flexcan_data_info_t dataInfo =
{ .data_length = len, .msg_id_type = FLEXCAN_MSG_ID_STD };

/*configure the RXMb*/
FLEXCAN_DRV_ConfigRxMb(INST_CANCOM1, mailbox, &dataInfo, messageId);
/*Install the callback function*/
FLEXCAN_DRV_InstallEventCallback(INST_CANCOM1, Callback,data_buf_struct);
/*Receive data for the specified ID using a specific mailbox*/
while(FLEXCAN_DRV_Receive(INST_CANCOM1, mailbox, data_buf_struct) != STATUS_SUCCESS)



Then I called this function to receive three different messages.

int main(void)
/*** Processor Expert internal initialization. DON'T REMOVE THIS CODE!!! ***/
PEX_RTOS_INIT(); /* Initialization of the selected RTOS. Macro is defined by the RTOS component. */
/*** End of Processor Expert internal initialization. ***/


/*** Don't write any code pass this line, or it will be deleted during code generation. ***/
/*** RTOS startup code. Macro PEX_RTOS_START is defined by the RTOS component. DON'T MODIFY THIS CODE!!! ***/
PEX_RTOS_START(); /* Startup of the selected RTOS. Macro is defined by the RTOS component. */
/*** End of RTOS startup code. ***/
/*** Processor Expert end of main routine. DON'T MODIFY THIS CODE!!! ***/
for(;;) {
if(exit_code != 0) {
return exit_code;
/*** Processor Expert end of main routine. DON'T WRITE CODE BELOW!!! ***/

void CANService(void)

Set_Pit_100ms(); /*Use the PIT to send message from chip every 100ms*/

/*receive three message*/
ReceiveCANData(1, 0x101, &test1,7);
ReceiveCANData(5, 0x105, &test2, 7);
ReceiveCANData(6, 0x106, &test3, 7);


But when I tested my code, there were some bugs.Here's my test code.


static void Callback(uint8_t instance,
flexcan_event_type_t eventType, uint32_t buffIdx,
flexcan_state_t *flexcanState)
/*Passing parameters with flexcanState,the parameter is the message buffer*/
flexcan_msgbuff_t * poninter_to_buf_struct = flexcanState ->callbackParam;
/*Define an array to receive data*/
uint8_t data1[8] = {0};
/*Assign values to arrays*/
int i = 0;
for (;i < poninter_to_buf_struct ->dataLen; i++)
data1 [i] = poninter_to_buf_struct ->data[i];
/*Processing received data*/
switch (eventType)
switch (buffIdx)
case 1:
/*When receiving the data of the corresponding bufIdx,
* the chip will use the mailbox 2 to send the data with
* the ID what 102, and the content is the received data,
*because the function FLEXCAN_DRV_ConfigTxMb() Configured to receive
*the specified ID using a specific mailbox

BSW_SendCANData(2, 0x102, data, 7);
BSW_ReceiveCANData(1, 0x101,
&test1, 7);
case 5:
BSW_SendCANData(3, 0x103, data, 7);
BSW_ReceiveCANData(5, 0x105, &test2, 7);
case 6:
BSW_SendCANData(4, 0x104, data, 7);
BSW_ReceiveCANData(6, 0x106, &test3, 7);


The result is an error as shown below.


The expected result is that when the chip receives the ID101 data, it should send the ID101 data back with ID102.The result was a mess.The ID102 returns the data of ID106 and ID103 returns the ID101's data.



I want to know how this problem occurs, how to deal with it, what should be the correct way to use interrupt processing to receive messages?


Thank you,