Setting 8Mhz clock speed on PIC16F684


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  1. #1
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    Default Re: Setting 8Mhz clock speed on PIC16F684

    Just to add, I based my last post on this article: http:// melabs.com/resources/pbpmanual/7_0.htm

    But I may have misinterpreted it, in that I thought PAUSE 1000 with DEFINE OSC 4 internal OSC would give one second delay and pause 1000 with DEFINE OSC 8 internal OSC would give 0.5 second delay.....

    So are we saying that the above PAUSE 1000 would both cause a one second delay?

    Is it only external Xtals/resonators that throw the internal timing off?

    Dave

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    Default Re: Setting 8Mhz clock speed on PIC16F684

    Is it only external Xtals/resonators that throw the internal timing off?
    no not at all.

    the only time it fails is when DEFINE OSC does not match the real osc frequency.

    Warning I'm not a teacher

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    Default Re: Setting 8Mhz clock speed on PIC16F684

    Thanks again Richard.

    So as long as I use DEFINE OSC X, PB knows and compensates for the change still giving the correct timings PAUSE etc?

    David

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    Default Re: Setting 8Mhz clock speed on PIC16F684

    Yes, That is correct. The PAUSE command is based on the OSC frequency. If you had an 4 Mhz. crystal connected and told PBP that the OSC was 8Mhz. the PAUSE command would give you 2 times the value entered into the PAUSE command.
    Dave Purola,
    N8NTA
    EN82fn

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    Default Re: Setting 8Mhz clock speed on PIC16F684

    Dave & Richard, thank you both for taking the time to reply, much appreciated.

    Dave

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