On 11/3/06, Andre Abelian <aabelian@mason-electric.com> wrote:
>
> Problem is that the sense pin (AN2, porta.2) is registering nearly the
> full
> AVdd when no panel is connected and then around 2-3V when the panel is
> connected  .
> ****
> while disconnected what voltage do you have on porta.1 ?
>
> ****


AVdd which is ~ 5V.

  Is this typical for a PIC uC?  The A/D conversion works,
> ****
> no. some things not right?
>
> ****
>
> but
> it seems like I'm going to have to tie my sense pin to a very weak pull
> down
>
> ****
> maybe you already have a pullup?
>
****



Thought you had to explicitly enable the pull-ups on the chip.  Barring any
internal pull-ups on the port, there is nothing on the line.


in order for it to register properly.  Does this sound right?
>
> ****
> no
> ****
> you need to add a delay to charge capacitors before conversion


There is a 1ms delay, which should far exceed any "Tad" time necessary on
the chip.

-- 

Shawn Wilton (b9 Systems)
http://b9Systems.com  <- New web page
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