I am required to transmit a standard Hex payload through serial com port to a device that has a CAN transceiver. The serial configuration is as follows: 500 kbps, 1, 8, None, 1.

The DUT has a CAN transceiver which only expects the Hex Payload and not a standard CAN frame. The Hex Payload contains it's own ID and CRC. I was wondering if there is an adapter module available that would allow me to send the Serial Data vi com port so I can communicate with the DUT.

I tried to communicate with the DUT using a standard CAN Frame (using NI8502 CAN module) and my DUT does not respond as it receives a lot of unnecessary data through CAN Frame.

  • \$\begingroup\$ Hi, Just for clarification: The UART format you describe (it's not RS-232 unless you have that electrical interface being used, and you don't mention it, so I removed that tag) says: "500 kbps, 1, 8, None, 1" That's probably 500 kbps, [something], 8 data bits, no parity, 1 stop bit. What is the meaning of the "1" you stated, where I wrote "[something]" in that list? Is that indicating 1 start bit? Thanks. \$\endgroup\$
    – SamGibson
    Jun 17, 2020 at 0:47
  • \$\begingroup\$ You need some manner of intelligent adapter for this, since the "serial" UART is an entirely different technlogy than CAN, with different signals, frames, voltage levels, everything. A CAN transceiver alone will do you little good, since it is just a dumb signal converter, translating the TTL/CMOS levels of the Tx/Rx signals from a CAN controller into a differential signal with CANH + CANL (2.5V +/- 1V). You can't just connect an UART signal into those Tx/Rx pins, because the only thing those signals have in common between UART and the CAN transceiver are the names. \$\endgroup\$
    – Lundin
    Jun 17, 2020 at 9:16
  • \$\begingroup\$ So you need to back off and review your specification once more. What does it say and does it make any sense? Because as it stands, your question doesn't. CAN transceivers don't "expect hex payload" or even CAN frames, they don't have any intelligence. As for why the CAN communication isn't working, there are countless of reasons and no telling what could be the cause without details. \$\endgroup\$
    – Lundin
    Jun 17, 2020 at 9:17
  • \$\begingroup\$ @SamGibson, Yes, [something] means Start bit. \$\endgroup\$
    – Rav
    Jun 17, 2020 at 17:56


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