At a guess, the two transducers are not adequately decoupled with respect to the power supply and I'm guessing the potentiometer is a fairly low resistance and the pressure sensor has a high resistance so that their respective current flow changes are very different.
Solutions could be to either 1) Change the power supply to something that can source a higher flow - is it a USB powered thing? 2) Put a big (33,000uF or 68,000uF) capacitors across each sensors supply close to it. On Thu, 12 Nov 2009 18:02:05 +0100 altern <alte...@gmail.com> wrote: > hi > > not a PD question I guess... i dont know much of electrical stuff. i am > connecting two analog sensors to the arduino. One is a pressure sensor > and the second a potentiometer, they are both from an old icube. > > i noticed that when i raise the potentiometer (analog pin 5) the > pressure sensor (analog pin 2) reports values ranging 0 to ~0.16 > increasing together as the potenciometer goes up. It is like some kind > of residual noise comming from pin 5 that goes into pin 0. > > the power cables of both sensors go together to 5v inlet of the arduino > and the ground cables go to ground pin, each of the data cable goes to > its separate analog pin. > > I am using arduino from Pure Data extended using latest Firmata, so i am > just filtering out any value smaller than 0.16 coming from analog pin 0. > > is there anything I am doing wrong? or is this normal? > > thanks > > enrike > > _______________________________________________ > Pd-list@iem.at mailing list > UNSUBSCRIBE and account-management -> > http://lists.puredata.info/listinfo/pd-list _______________________________________________ Pd-list@iem.at mailing list UNSUBSCRIBE and account-management -> http://lists.puredata.info/listinfo/pd-list