PIC24 ECAN Help

[Bluedog01]

Hi,

I am using ECAN on P24EP512GU810. It is connected to an existing bus with two other nodes. If I set mode to NORMAL it decodes ok.

I want to use Listen Only mode so that my node is passive ( doesn't send and packets - including ACK ). I have attached the example code which works fine.

By changing the last line from

ECAN1SetOperationMode(_ECAN_MODE_NORMAL, 0xFF); // set NORMAL mode

to

ECAN1SetOperationMode(_ECAN_MODE_LISTEN, 0xFF);

I was hoping to change operation to passive but still decode packets.

Any help appreciated.

Andy

Code: Select all

/* Clear Interrupt Flags */

  IFS0=0;
  IFS1=0;
  IFS2=0;
  IFS3=0;
  IFS4=0;

  /* Enable ECAN1 Interrupt */

  IEC2bits.C1IE   = 1;                             // enable ECAN1 interrupts
  C1INTEbits.TBIE = 1;                             // enable ECAN1 tx interrupt
  C1INTEbits.RBIE = 1;                             // enable ECAN1 rx interrupt

  PORTB = 0;                                       // clear PORTB
  TRISB = 0;                                       // set PORTB as output,
                                                   // for received message data displaying

  Can_Init_Flags = 0;                              //
  Can_Send_Flags = 0;                              // clear flags
  Can_Rcv_Flags  = 0;                              //

  Can_Send_Flags = _ECAN_TX_PRIORITY_0 &           // form value to be used
                   _ECAN_TX_XTD_FRAME &            // with CANSendMessage
                   _ECAN_TX_NO_RTR_FRAME;

  Can_Init_Flags = _ECAN_CONFIG_SAMPLE_THRICE &    // form value to be used
                   _ECAN_CONFIG_PHSEG2_PRG_ON &    // with CANInitialize
                   _ECAN_CONFIG_XTD_MSG &
                   _ECAN_CONFIG_MATCH_MSG_TYPE &
                   _ECAN_CONFIG_LINE_FILTER_OFF;

  RxTx_Data[0] = 9;                                // set initial data to be sent
  ECAN1DmaChannelInit(0, 1, &ECAN1RxTxRAMBuffer);  // init dma channel 0 for
                                                   // dma to ECAN peripheral transfer
  ECAN1DmaChannelInit(2, 0, &ECAN1RxTxRAMBuffer);  // init dma channel 2 for
                                                   // ECAN peripheral to dma transfer
  ECAN1Initialize(1, 3, 3, 3, 1, Can_Init_Flags);  // initialize ECAN
  ECAN1SetBufferSize(ECAN1RAMBUFFERSIZE);          // set number of rx+tx buffers in DMA RAM

  ECAN1SelectTxBuffers(0x000F);                    // select transmit buffers
                                                   // 0x000F = buffers 0:3 are transmit buffers
  ECAN1SetOperationMode(_ECAN_MODE_CONFIG,0xFF);   // set CONFIGURATION mode

  ECAN1SetMask(_ECAN_MASK_0, -1, _ECAN_CONFIG_MATCH_MSG_TYPE & _ECAN_CONFIG_XTD_MSG);         // set all mask1 bits to ones
  ECAN1SetMask(_ECAN_MASK_1, -1, _ECAN_CONFIG_MATCH_MSG_TYPE & _ECAN_CONFIG_XTD_MSG);         // set all mask2 bits to ones
  ECAN1SetMask(_ECAN_MASK_2, -1, _ECAN_CONFIG_MATCH_MSG_TYPE & _ECAN_CONFIG_XTD_MSG);         // set all mask3 bits to ones
  ECAN1SetFilter(_ECAN_FILTER_10, ID_2nd, _ECAN_MASK_2, _ECAN_RX_BUFFER_7, _ECAN_CONFIG_XTD_MSG);  // set id of filter10 to 2nd node ID
                                                                                              // assign mask2 to filter10
                                                                                              // assign buffer7 to filter10
  ECAN1SetOperationMode(_ECAN_MODE_NORMAL, 0xFF);  // set NORMAL mode

[Bluedog01]

Further investigation shows this device actually crashes the communication on the bus when set to Listen mode.... It is supposed to be passive but it certainly isn't.

Andy