On Sat, Jun 12, 2004 at 09:40:22AM +0200, Wouter van Ooijen wrote:
> > Chaps, can someone tell me if the LVP / RB5 pin on a
> > PIC18F452 needs to be tied low?
>
> The problem is your word 'needs'. I don't know whether it is realy
> needed, like I don't know whether that 100 nF cap near the PIC is
> needed, or whether you realy need those caps at the crystal. But I sure
> know that I'd rather keep them all in place and not risk problems.
>
> > If I do tie RB5 low, then I lose a pushbutton, since I have a
> > bank of 4
> > switches on RB4,5,6,7 which use the internal weak pull-ups, with the
> > switches pulling low through 1k when pressed.
>
> Use a pull-down that is weaker than the internal weak pull-ups. Or use
> Wisp628 which has a dedicated LVP pull-down line :)

Wouter, I need some separation clarity from you here.

I'm clear on the LVP pin problem when programming. See my other post. But are
you saying that there's a glitch issue when simply using a HVP programmed
part with LVP config bit clear? I haven't seen any errata lately that indicates
that the LVP pin is active at all when the config bit is clear. Do you have
evidence to the contrary? Please advise.

BAJ

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