switch the voltage to the pots and connect the taps with a diode all
together to one pin, you only need one analog input

Peter

> -----Original Message-----
> From: pic microcontroller discussion list
> [mailto:PICLIST@MITVMA.MIT.EDU]On Behalf Of Stewart Pye
> Sent: Saturday, July 31, 1999 8:23 PM
> To: PICLIST@MITVMA.MIT.EDU
> Subject: ADC multiplexing
>
>
> Hi...
>
> I need 14 analog inputs on a 16F877. My original plan was to use a 4051
> analog mux one one of the analog inputs. After using one for a DAC I'm
> having second thaughts...
>
> To get it fast enough Vdd needs to be 12V, then you need open collector
> buffers to interface the address lines. Any ideas for a better approach?
> Serial AtoD maybe. The application is a midi controller. The voltage is
> read off 14 pots. If it has changed the value is output the
> serial port. So
> it has to be fast enough to track multiple knobs moving simultaneously.
>
> Thanks,
> Stewart Pye.