i just tie the input with a 1Mohm resistor to either Vcc or Gnd. if either
max or zero count is outside the normal reading then you know that either
the sensor failed or is not connected.


michael


-----Original Message-----
From: Dave Celsnak <x93celsnak@WMICH.EDU>
To: PICLIST@MITVMA.MIT.EDU <PICLIST@MITVMA.MIT.EDU>
Date: Saturday, December 06, 1997 3:46 AM
Subject: Re: Floating Inputs


>Does the PIC require it's Analog-to-Digital Convertor inputs to be tied
>down if unused?   I am using the PIC 16c72 with 5 A/D Channels.  If the
>consumer of my product forgets to install one of the analog inputs, will
>the on-chip A/D's have any problems 'floating'?
>
>Thank you,               6500
>                              7000
>Dave Celsnak                    ___7500
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