Forgot the first [ in [PIC]:


> Hi,
>
> I'm having problems programming my PICs.
>
> I have connected the MCLR pin of my PIC16F876 through a 10k resistor and a
> BAS16 diode to 5V. The programmer connection is straight to MCLR pin.
>
> I cannot get this to work.
>
> Now I understand is says I need a Schottky diode but can someone explain
> what difference a Shottky diode makes over a normal signal diode? (Sorry
to
> be dumb)
>
> When I say I cannot get this to work I mean with the XTAL taken off the
> board the PIC programs O.K. I place the XTAL back on and now the program
> runs but I cannot get it to program the PIC with the XTAL on and the above
> circuit for MCLR. I suspect it's not putting the PIC into programming mode
> by pulling MCLR low or something? Will a Schottky diode make tat much
> difference? I have no problem buying a Schottky diode (BAT54 or BAT17 ?)
and
> trying that.
>
> I used this circuit for a 16F84 and never had any problems (was I just
> lucky?)
>
> Also I didn't have a capacitor externally to provide an R/C delay upon
> powerup as I've set the power up timer instead. Is this correct? Should I
> have both?
>
> I'm using a PICPRO16 hardware board if that helps.
>
> Thanks
>
> Peter

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