MCP3301 A/D converter SPI reading


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  1. #1
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    Default Re: MCP3301 A/D converter SPI reading

    Yes, Richard is correct. I forgot to mention you have to adjust the value to the byte, word or whatever width you have.

    So the sign is the left most bit but the rest should also be 1. Remember we reverse the bits to get the absolute value disregarding the left most, sign bit.

    Seems confusing at first, but has its logic.

    Ioannis
    Last edited by Ioannis; - 9th February 2024 at 11:11.

  2. #2
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    Thumbs up MCP3301 A/D converter SPI reading

    Got it now!

    Thanks a lot
    Roger

  3. #3
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    Default Re: MCP3301 A/D converter SPI reading

    Remember we reverse the bits to get the absolute value disregarding the left most, sign bit
    To convert a 2's compliment negative value to a positive number, invert all the bits (NOT) and add 1.

    For example 2's compliment -1 = FFFF
    invert = 0000, add 1 = 0001

  4. #4
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    Default Re: MCP3301 A/D converter SPI reading

    I was reffering to the left most bits but yes. Absolutely correct, to convert a positive to negative after reversing all bits you add one.

    Ioannis

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