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    CAN Protocol to FPGA

    Hi,

    In my project , I need to adapt an FPGA card to read data from 4 CAN network at least. Beacuse i didn't found an FPGA including more than 2 CAN controllers. i ´m wondering if there is a solution for this. I read that is possible to emumate CAN bus with RX TX I/O of the fpga with an IP core but i dont't find more information of how it is possible.
    Also , i don't know if we can use the protocole CAN only with the GPIO of the fpga.

    Can any of you guys suggest how to perform this ?


    thx..

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    Re: CAN Protocol to FPGA

    What FPGA vendor has 2 CAN hard IP blocks? I don't think I've ever seen such a device before.

    Usually an FPGA doesn't have much hard IP beyond multi-gigabit transceivers, PLLs, DSP blocks, block memroy, PCI end points, and perhaps a processor core. Are you sure you aren't confusing FPGAs with a microcontroller with integrated CAN?

    If you want one or more CAN controller(s) you have to implement them in the FPGA fabric logic, therefore you are only limited by the number of controllers that fit within the device resources.



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    Re: CAN Protocol to FPGA

    No , I'm not confusing the FPGA with a microcontroller. A FPGA with 2 Can controllers exist here is the link for what I found :
    http://www.devboards.de/en/home/boar...cle/dbc5cefa7/

    Now, I don't know how to use an FPGA with CAN (more than two). When you say implement in the FPGA Fabric logic do you mean IP Cores ?



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    Re: CAN Protocol to FPGA

    The FPGA doesn't have CAN there are 2 CAN transceivers on the board. Different thing entirely.

    If you want 4 CAN buses then you'll have to find a board with 4 CAN transceivers or make a board with 4 transceivers.

    The FPGA design only needs IP to interface with those CAN transceivers.



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    Re: CAN Protocol to FPGA

    Ah ! that's what i meant sorry !

    So restating my problem : I need an FPGA with more than 4 CAN bus. Can I make these CAN bus only with the GPIO of the FPGA ?



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    Re: CAN Protocol to FPGA

    CAN is not very high speed, so normal I/O pins on the FPGA (GPIO) can be used, but the FPGA pins are not electrically compatible with the CAN bus.
    Each controller needs an external CAN transceiver. It is not a problem to fit 4 CAN controllers in an FPGA.

    Search for "SN65HVD230" on Aliexpress or Ebay and you will find many boards that will solve the transceiver problem for you.



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    Re: CAN Protocol to FPGA

    Hi Elhb

    If there isn't 4-CAN Transceivers IC on a DEV-board in the market that meet your needs, probably you will have to design custom one.
    But before doing that i'dd suggest you to make design review of your application, maybe you can verify your code with 2-CANs and expend it on your custom board further.

    Gil



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