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     Corne--

     AN1 on the PIC14000 cannot be used as an analog input if the
     level-shift network is disabled.  AN5 behaves the same way. This is
     explained in the PIC14C000.pdf device errata which is available on the
     Microchip web site (www.microchip.com).  Have you set the LSOFF bit
     (SLPCON<4>)?  If so, this will cause AN1 to go to five volts,
     rendering it unusable as an analog input...as you have experienced.

     There are two ways to resolve this problem.  Either use a different
     A/D channel, or if you must use AN1, follow the steps below.  I have
     also attached the complete errata to this message.  Just use Adobe
     Acrobat to read it.


     1) Ensure the LSOFF bit (SLPCON<4>) is cleared.
     2) Ensure a good zero-level on AN1 and/or AN5 by setting the ADZERO
        bit(ADCON0<0>).
     3) Perform an A/D conversion as normal and keep the count from ADCAPH
        and ADCAPL in user-defined RAM. This is the representative digital
        count for the exact level-shift value.
     4) Enable the signal of interest onto AN1.
     5) Perform another A/D conversion and keep the count in ADCAPH and
        ADCAPL. This is the rep-resentative digital count for the sum of
        the signal of interest and the exact level-shift value.
     6) Subtract the level-shift count from the representative count for
        the sum.
     7) This result will be the representative count for the signal of
        interest alone.

     Good luck.  I believe this explanation should resolve the problem.
     Please let me know, either directly or via PICLIST.

     Regards,

     Wes Reid
     Sr. Apps Engineer
     wes.reid@microchip.com
     (602)786-7562
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