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How to calculate Ckecksum

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  • Official comment
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    Ellie Best

    Hi Edgar,

     

    To calculate the checksum, you need to add the hex words as you have been doing, but also b58c (see checksum in data structure, Integrator's Guide). So your calculation will be:

    b58c + a521 + 4f00 + 4517 + ... + 0808 = xxxx

     

    You then do a modulo FFFF on the result since the max word is FFFF:

    checksum = MOD(xxxx,FFFF) = yyyy

     

    Best regards,

    Ellie

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  • Avatar
    EDGAR OSORIO

    You can send me a example . because Integrator's Guide do not show it.

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  • Avatar
    Ellie Best

    If we just look at the first line of data, the checksum calculation would be:

    a5 21 4f 00 45 17 14 15 20 05 00 00 00 00 92 00

    b58c + a521 + 4f00 + 4517 + 1415 + 2005 + 0000 + 0000 + 9200 = 2 b4de

    MOD(2b4de,ffff) = b4e0

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