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    6/17/2021 5:27 am  #1

    tsenga
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    Registered: 7/24/2017
    Posts: 28

    Expedition Protocol - checksum

    I'm exploring using the expedition protocol both to receive data from Expedition and send commands to it. I couldn't find details of the checksum used on each line, could I get the details of it? I presume that the checksum needs to be correct for Expedition to process commands?

     

    6/17/2021 12:43 pm  #2

    Nick
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    Registered: 9/16/2015
    Posts: 3,286

    Re: Expedition Protocol - checksum

    It is exactly as for the NMEA 0183 checksum. For example

    https://en.wikipedia.org/wiki/NMEA_0183#C_implementation_of_checksum_generation

     

    6/18/2021 1:48 pm  #3

    tsenga
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    Registered: 7/24/2017
    Posts: 28

    Re: Expedition Protocol - checksum

    Thanks Nick. It looks like you include the expedition '#' as part of the checksum whereas NMEA excludes the initial '$'. 

    Follow-up, is there a listing of the channel names against channel id anywhere? I think I can just call GETCHANNELNAME on each of them, but since there are 204 or so, I thought I'd check whether it was already available somewhere.

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    6/18/2021 2:17 pm  #4

    Nick
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    Re: Expedition Protocol - checksum

    Yes, that is correct. No idea why it was done that way.

    There isn't sorry. A loop over that should be easy.

     

     

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