So if the MCLR pin is tied to Vdd, then whats to keep Vdd from rising to 13v
when the chip enters ICSP programming mode?  To me it seems like this will
just fry my chip!  The mid-range reference manual shows a typical POR
circuit which confirms what you're saying, but it doesn't mention the
effects on ICSP.  Under the ICSP section it shows a diode to block the ICSP
programming voltage from reaching Vdd.  So here's my plan for the moment:
Leave the MCLR connected to the ICSP header, then attach MCLR through a
diode to Vdd, which should give the MCLR pin no opportunity to reset.

Sound good?


----- Original Message -----
From: "Jake Anderson" <grooveee@OPTUSHOME.COM.AU>
To: <PICLIST@MITVMA.MIT.EDU>
Sent: Wednesday, April 14, 2004 10:00 PM
Subject: Re: [PIC:] Odd behavior


> 13V is only for programming
> for general opperation it should be tied high (5v/vcc)
> then pull to low to reset the PIC
>
> (might want to check that i always get it mixed up lol)
> its /Mclr so make your own mind up lol
>
> -----Original Message-----
> From: pic microcontroller discussion list
> [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Robert B.
> Sent: Thursday, April 15, 2004 12:51 PM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: Re: [PIC:] Odd behavior
>
>
> The MCLR pin is just attached to the ICSP header, so I guess it is
floating.
> I was under the impression that it needed about 13v on it to affect
> anything, though... is this not true?
>
>
>
>
> ----- Original Message -----
> From: "Ken Pergola" <no_spam@LOCALNET.COM>
> To: <PICLIST@MITVMA.MIT.EDU>
> Sent: Wednesday, April 14, 2004 9:42 PM
> Subject: Re: [PIC:] Odd behavior
>
>
> > Robert B wrote:
> >
> > > I've been getting some really strange behavior out of a 16F873A.
> >
> > Hi Robert,
> >
> > Regarding the /MCLR pin, what does your PIC's reset circuit look like?
> > Is it floating by chance?
> >
> > Best regards,
> >
> > Ken Pergola
> >
> > --
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