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I am using Teensy 4.1 and need to communicate with motor driver which supports CAN and RS-485. In teeny4.1 CAN is supported yet it requires CAN transceiver whereas if I want to use RS-485 I need to add UART to RS-485 converter.

So I thing using UART to RS-485 converter will limit the communication speed because of hardware Serial interface of teensy. Now the question is using CAN transceiver will limit the communication speed too ? I am planning to use SN65HVD230 as CAN transceiver.

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  • \$\begingroup\$ Converters, as in gateways, listeners etc introduce delays. Transceivers do not, they are designed to support the baudrates used by the bus. \$\endgroup\$
    – Lundin
    Commented Jun 23, 2022 at 9:33

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CAN tranceiver and RS485 trasceiver are both transceivers, you need one anyway to convert MCU logic level interface to whichever physical interface you want to use.

You need to choose the transceiver based on what speeds you want to communicate, as there are transceivers for fast bit rates and slow bit rates.

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    \$\begingroup\$ "as there are transceivers for fast bit rates and slow bit rates" Careful with that in the context of CAN. There's traditionally "fault-tolerant" (5V levels) vs "high speed" CAN, where "high speed" refers to normal/classic CAN. And lately also CAN FD and CAN XL. All of these are physically different hardware layers and transceivers are not necessarily compatible between them. \$\endgroup\$
    – Lundin
    Commented Jun 23, 2022 at 9:36
  • \$\begingroup\$ Thank you for extra info. I want to highlight the comment made by Lundin above. If I use RS-485 to TTL converter that should definitely introduce more delay which will be less in transciever. Simply, if I have option to choose between transceiver and converter, should I choose transceiver? (Im asking in general, irrespective of module's capabilities.) \$\endgroup\$
    – dharmikP
    Commented Jun 23, 2022 at 9:55
  • \$\begingroup\$ It is unknow what you mean by converter or transceiver. If you want to connect MCU to CAN bus or RS485 bus, you need a PHY chip, which is the transceiver for the interface and it converts voltage levels for connecting to MCU. Same thing. \$\endgroup\$
    – Justme
    Commented Jun 23, 2022 at 10:24
  • \$\begingroup\$ @dharmikP 'transceiver' vs 'converter' is usually just different terminology for the same thing. It's not correct to say that one would introduce more delay than the other. \$\endgroup\$
    – brhans
    Commented Jun 23, 2022 at 12:13
  • \$\begingroup\$ Okk. I take this as, if I want make comparison between this two I have to dig deeper into specification of module and working of system, as there is no streight away answer. Thank you. \$\endgroup\$
    – dharmikP
    Commented Jun 24, 2022 at 3:48

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