You are right! After this I checked, and what is actually happening is that
when I put the scope probe on the xtal the osc stops. The real problem is
the way startup happens (I think). I am not using mclr and have enabled the
startup timer. I will not mod the design to use mclr so I can set the
startup reset time by hardware. I assumed that the erratic operation was due
to the osc.

Thanks to all that replied.
George

----- Original Message -----
From: "Ken Pergola" <no_spam@LOCALNET.COM>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Tuesday, August 26, 2003 10:23 PM
Subject: Re: [PIC:] 18f1220 xtal osc.


> Hi George,
>
> As few questions:
>
> 1) It's hard to tell from your post, but I'm curious to know what led you
to
> the conclusion that the crystal is starting erratically? (I'm not trying
to
> be a meanie here -- the answer to this question might eventually lead to
> your solution.)
>
> 2) Is the crystal definitely a parallel-cut type?
>
>
> Regards,
>
> Ken Pergola
>
>
>
>
> -----Original Message-----
> From: pic microcontroller discussion list
> [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of gtyler
> Sent: Tuesday, August 26, 2003 4:15 PM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: Re: [PIC:] 18f1220 xtal osc.
>
>
>  Hi all,
>             I'm looking for suggestions: I have a pic18f1220 running in
> HSPLL mode at 10 Mhz, and yes, I do need the speed. I have been unable to
> make the xtal start reliably. I found some info on uchip's web site, but
in
> spite of changing the caps to all values between 12 and 47P it still
starts
> erratically. also tried changing xtal manifacturers. Has anyone else had
> similar problems, or has some suggestions?
>
> Regards,
>             George
>
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