CAN Grundsatzfrage bitte um HILFE!

main.c

  // CAN RX Filter

  CAN_FilterInitTypeDef CAN_FilterInitStructure;

  CAN_FilterInitStructure.CAN_FilterNumber = 0;

  CAN_FilterInitStructure.CAN_FilterMode = CAN_FilterMode_IdMask;

  CAN_FilterInitStructure.CAN_FilterScale = CAN_FilterScale_32bit;

  CAN_FilterInitStructure.CAN_FilterIdHigh = 0x0200 << 5;

  CAN_FilterInitStructure.CAN_FilterIdLow = 0x0000;

  CAN_FilterInitStructure.CAN_FilterMaskIdHigh = 0xFFFF;

  CAN_FilterInitStructure.CAN_FilterMaskIdLow = 0xFFFF;

  CAN_FilterInitStructure.CAN_FilterFIFOAssignment = 0;

  CAN_FilterInitStructure.CAN_FilterActivation = ENABLE;

  CAN_FilterInit(&CAN_FilterInitStructure);

stm32f10x_it.c

  void USB_LP_CAN1_RX0_IRQHandler(void)

            {

 CanRxMsg canRxMessage;

 CAN_Receive(CAN1, CAN_FIFO0, &canRxMessage);

 switch(canRxMessage.StdId)

          {

  case 200: // Mode Command

  WriteRegisters[0][0] = canRxMessage.Data[0];

        WriteRegisters[0][1] = canRxMessage.Data[1];

  WriteRegisters[0][2] = canRxMessage.Data[2];

        WriteRegisters[0][3] = canRxMessage.Data[3];

                break;

             default:break;

              }

             CAN_ClearITPendingBit(CAN1, CAN_IT_FF0);

            }