SHIFTOUT MSB/LSBFIRST clarification


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  1. #1
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    Default Re: SHIFTOUT MSB/LSBFIRST clarification

    completely wrong , the first bit is on the left
    Warning I'm not a teacher

  2. #2
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    Default Re: SHIFTOUT MSB/LSBFIRST clarification

    could you please check in the real situation:

    connect the PIC DATA output to scope ch_1
    connect the PIC clock output to scope ch_2 and set the trigger to this channel.
    Tranmit bin 00000011 ( dec 3 ) \8 selecting MSB FIRST. and insert a small delay in the main loop just for better scope triggering. My scope is a old style !

    What do you see on the scope ? 00000011 or 11000000 ?
    Or better: do you see "11" to the right side or to the left side of the scope ?

    Thanks for helping
    regards

  3. #3


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    Default Re: SHIFTOUT MSB/LSBFIRST clarification

    You will send 00000011.

  4. #4
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    Default Re: SHIFTOUT MSB/LSBFIRST clarification

    Hi Peter,
    could you please clarify better ?
    ( my English is not a first language )
    Thanks

  5. #5
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    Default Re: SHIFTOUT MSB/LSBFIRST clarification

    iT IS MY FAULT:
    Richard explanation is correct as usual !
    Thanks for all.
    All the best
    regards,
    Bye

  6. #6
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    Default Re: SHIFTOUT MSB/LSBFIRST clarification

    In the first post you said the number was 128 (10000000 in binary) so the MSB is indeed a '1'.

    But on the last post you saw a number 3 (00000011 in binary) so the MSB is a '0'.

    Ioannis

  7. #7
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    Default Re: SHIFTOUT MSB/LSBFIRST clarification

    thanks for the response,
    I had on my mund a shift register that will receive the serial stream from the PIC and I did associated the scope display to the shift register...
    I was in error when I thought that the first bit on the left hand side of the scope is the last transmitted by the PIC: the first bit bit on the left of the scope is the first transmitted and the last bit to the right is the last transmitted.
    Again, it was my fault .
    Thanks for the assistance.
    regards,Bye

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