M400 CAN Bus and PIC32 Microcontroller

[carbon]

Hello,

I am trying to read data from a Motec M400 with a PIC32 dev board with a CAN transreceiver. M400 is set to Custom data set 1 according to the directions on this page: http://www.race-technology.com/wiki/index.php/ECUType/MotecM400M600M800CAN and I have set the CAN configuration on the dev board as such:

Code: Select all

void CAN1Init(void)
{
    CAN_BIT_CONFIG canBitConfig;
    UINT baudPrescalar;
    CANEnableModule(CAN1, TRUE);
    CANSetOperatingMode(CAN1, CAN_CONFIGURATION);
    while(CANGetOperatingMode(CAN1) != CAN_CONFIGURATION);

    // Standard Values
    canBitConfig.phaseSeg2Tq = CAN_BIT_3TQ;
    canBitConfig.phaseSeg1Tq = CAN_BIT_3TQ;
    canBitConfig.propagationSegTq = CAN_BIT_3TQ;
    canBitConfig.phaseSeg2TimeSelect = TRUE;
    canBitConfig.sample3Time = TRUE;
    canBitConfig.syncJumpWidth = CAN_BIT_2TQ;

    // Set speed to 1 Mbit/s
    // SYSTEM FREQ = 80,000,000 (80 MHz)
    // CAN_BUS_SPEED = 100,000
    CANSetSpeed(CAN1, &canBitConfig, SYSTEM_FREQ, CAN_BUS_SPEED);

    // 256 bytes of storage space
    CANAssignMemoryBuffer(CAN1, CAN1MessageFifoArea, (2*8*16));

    CANConfigureChannelForTx(CAN1, CAN_CHANNEL0, 8, CAN_TX_RTR_DISABLED,
            CAN_LOW_MEDIUM_PRIORITY);

    // Configure Filter to read Battery Voltage
    CANConfigureChannelForRx(CAN1, CAN_CHANNEL1, 8, CAN_RX_FULL_RECEIVE);

    CANConfigureFilter(CAN1, CAN_FILTER0, 0x5F3, CAN_SID);

    CANConfigureFilterMask(CAN1, CAN_FILTER_MASK0, 0x7FF, CAN_SID, CAN_FILTER_MASK_IDE_TYPE);

    CANLinkFilterToChannel(CAN1, CAN_FILTER0, CAN_FILTER_MASK0, CAN_CHANNEL1);

    CANEnableFilter(CAN1, CAN_FILTER0, TRUE);

    CANEnableChannelEvent(CAN1, CAN_CHANNEL1, CAN_RX_CHANNEL_NOT_EMPTY, TRUE);

    CANEnableModuleEvent(CAN1, CAN_RX_EVENT, TRUE);

    INTSetVectorPriority(INT_CAN_1_VECTOR, INT_PRIORITY_LEVEL_4);
    INTSetVectorSubPriority(INT_CAN_1_VECTOR, INT_SUB_PRIORITY_LEVEL_0);
    INTEnable(INT_CAN1, INT_ENABLED);

    CANSetOperatingMode(CAN1, CAN_NORMAL_OPERATION);
    while(CANGetOperatingMode(CAN1) != CAN_NORMAL_OPERATION);   
}

I am looking at byte positions 4-5 on Channel 11 (battery voltage). However I am not getting any messages with that Message ID, I am not sure why I am not receiving any data since I can hook it up to the computer and read the battery voltage.

Any help on this matter will be appreciated.

Thank you.

[Polux RSV]

Code: Select all

// Set speed to 1 Mbit/s
    // SYSTEM FREQ = 80,000,000 (80 MHz)
    // CAN_BUS_SPEED = 100,000
    CANSetSpeed(CAN1, &canBitConfig, SYSTEM_FREQ, CAN_BUS_SPEED);

Is CAN_BUS_SPEED set at 1'000'000 in another source or header file?

Masks and filters are the most difficult part of can. First try to receive anything on your board by disabling any filters und masks. When you have reception working, activate masks and filters.

Hope this helps

Angelo

[carbon]

Sorry that was a typo, the real speed is set to 1,000,000 to set it to 1 Mbit/s. I have tried turning off all filters and mask to receive data with no luck. Someone mentioned it may be a timing problem. I am going to try with a different timing scheme that Microchip recommends. Any other ideas as to whats wrong?

Thanks,
carbon