On 07-Jan-12 00:47, Jan-Erik Soderholm wrote:
>
>
> Adam Walley wrote 2012-01-06 12:12:
>> Ok. I ran some tests and confirmed that the MCLR pin was indeed resettin=
g
>> the code,
>
> How ?
> It does sound as if you do not have any MCRL pullup resistor !?

Yes, there is clearly no pull up on his schematic which shouldn't be a=20
problem if he is using internal MCLR.

>
>
>> suggesting that the added noise caused by connecting the ground
>> wire from the PC (or pretty much anything) was preventing the PIC from
>> operating correctly. Lesson learned.
>>
>
> Not sure...
>
>> I have re-programmed the chip with the _MCLRE_OFF statement in my config=
..
>
> Note that Microship still recomends an external pullup. At least in
> the 16F690 datasheet.
>

I can't find that in my 41262a.pdf datasheet, can you please say where=20
they recommend that?
I can only find where they advise against connecting external MCLR to=20
Vcc directly due to external MCLR being very sensitive to overvoltage.

Djula
--=20
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