External clock on 16f819 problem.


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  1. #1
    Join Date
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    Default Re: External clock on 16f819 problem.

    I've studied the datasheet time and time again, I just don't get it. I need some help to understand what I'm missing here.

    The LCD still gives one line with the code and fuses as mentioned in posts above.

    BUT I can't see what's wrong.

    I need the settings as follows:-

    PortA.0 <----- ADC in
    PortA.1 NC
    PortA.2 -------> LCD RS
    PortA.3 -------> LCD Enable
    PortA.4 NC
    PortA.5 NC
    PortA.6 NC
    PortA.7 <------ EXT Osc in (Working)

    PortB.0 RW (Low, working)
    PortB.1 NC
    PortB.2 -----> LCD D6
    PortB.3 -----> PWM Out
    PortB.4 -----> LCD D4
    PortB.5 ------> LCD D5
    PortB.6 <---- clk count in for a ref frequency to compare against external clock using tmr
    PortB.7 ------> LCD D7

    I have set ADCON1=%10001110 without this the LCD is blank.

    I've tried other settings but I'm now completely confused.

    Can someone please help.

  2. #2
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    Default Re: External clock on 16f819 problem.

    I posted in the LCD_Anypin thread.

    My code with LCD_Anypin works with a 10mhz crystal oscillator but produces strange results on the LCD with EXTCLK.

  3. #3
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    Default Re: External clock on 16f819 problem.

    I have set ADCON1=%10001110 without this the LCD is blank.

    Datasheet page 83, section 11-0.

    Read settings for ADCON0 and ADCON1.

    At a glance, ADCON1 looks good, I think you need to set ADCON0 as well.

    Robert
    Last edited by Demon; - 27th January 2012 at 17:21. Reason: corrected

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