/tilted/ Posted July 16, 2008 Report Share Posted July 16, 2008 10khm are needed between the 5v inputs to Pin3 and GND to pin1 (unless you opt for tilted solution but that s another beast).Pin 3 has Not quite true.The AIN pins (all of them) need a voltage between 0v and 5v.This voltage is used to charge a known-value capacitor inside the PIC, and the charge here is 'read' by the pic (at least, this is the most likely option, to be honest I haven't checked, but this is how most low-cost AD converters work.) The point is, the PIC doesn't care what type of pot you have. It wants a voltage between Vss and Vdd, and will convert this into a 10 bit number. Of course, if you have a jittery pot, this will happen more often than is needed.So, what you could do is to have a 33k pot, connected to Vss at one end, the other end connected to a trimmer, then perhaps a 'safety resistance, then whatever voltage, say 9V, 12V, 15V... The junction between the "top" of the pot might also benefit from a schottky diode to Vdd, preventing the 'restricted' pot from feeding the pic more than Vdd (which could be an issue).You position the main pot so that the (back) position is at Vss, then you adjust the trimpot so that the highest voltage from the main pot, at the extent of it's travel, is Vdd. Problem fixed bender is a genius stop crying leela. Quote Link to comment Share on other sites More sharing options...
JMS Posted July 16, 2008 Report Share Posted July 16, 2008 arcade controls -> 10k, 90 degrees of movement... they aren't cheap though... still looking for another source that isn't mil-spec-extra-expensive-so-teenagers-don't-break-your-arcade-machine kinda prices...@cronic: i see you use a lot of open source programs, why don t you jump on the Kicad bandwagon?cimo, i have been toying with PCB, eagle is pretty close to working with autocad to which i am kinda partial. kicad is something i have not looked at yet, though i do have it installed. i really like eagle's "type what you want to do" process for building schematics, no icons! Quote Link to comment Share on other sites More sharing options...
stryd_one Posted July 16, 2008 Report Share Posted July 16, 2008 they aren't cheap though... Well, 90degree pots have to be 3* as accurate as the same pot in 270degree throw.... Quote Link to comment Share on other sites More sharing options...
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