Using Different Xtal Frequencies


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  1. #1
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    bobsimpson Guest

    Default Using Different Xtal Frequencies

    Hi all,

    I thought here goes give the new forum a go!

    Is it possible to use xtal frequencies other than the standard ones listed in the manual (4,8,12,etc). For example - I can get 12.5Mhz xtal’s for next to nothing.

    I can easily recalculate pause times within the basic program but how to change things like the RS232 serial timings have me stumped?

    Is there something I can change in PBP to enable me say to DEFINE freq as 25Mhz but the software divides by 2?

    Any thoughts appreciated,
    Thanks,
    Bob.

  2. #2
    Join Date
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    You could give it a go setting PB to 25MHz.

    The problem is everything will be twice as slow... so Pause 1000 will actually give you two seconds in real time.

    This also means that Setting 9600 baud will in reality give you 4800.

    Since you've nothing to lose, breadboard up some sample circuits and try it. Come back and tell us if it works.

    Melanie

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