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  1. #1
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    Icd2 Clone : Question ?

    Hi,

    I saw strange something in the Schematic ,In MCu PIC16F877A-I/P there is only one pin of the crystal is connected and the other is not connected...can anyone explain this to me :)

    ??


    thx

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  2. #2
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    Icd2 Clone : Question ?

    Poorly drawn schematic perhaps. Can you post the image?



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    Re: Icd2 Clone : Question ?

    Quote Originally Posted by blueroomelectronics
    Poorly drawn schematic perhaps. Can you post the image?
    Hi,

    No it wasn`t ,,I made ICD2 of PiCs design and only one pin was connected then when i tried to look in potyo design i found its the same.

    below is potyo schematic screenshot



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  4. #4
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    Icd2 Clone : Question ?

    yes all is ok, and is one pin because the buffer output of PIC 4550 is the input of 877A and this works as external clock an not as oscillator



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    Re: Icd2 Clone : Question ?

    Quote Originally Posted by folks
    yes all is ok, and is one pin because the buffer output of PIC 4550 is the input of 877A and this works as external clock an not as oscillator
    But is it stable design ?.... and if i want to put crystal instead of this is there any way for that ?

    thx



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  6. #6
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    Icd2 Clone : Question ?

    Yes, is very stable. here is the internal invert buffer:


    And yes you can put a crystal instead of a external clock but you waste your money and your time.



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