> > Hi!
> >
> > > the resistor trick works quite well for it.  Rather than seating the
> > > pieces in a hole, have a little plug on the bottom that fits into
> >
> > On a timed match, there is no extra time for plugging the pieces :)
>
> Hey, I'm the guy who first thought about this resistor solution.
> Mike's post inspired me, so now I have an idea how it could still work.
> You don't have to plug the figures in the chessboard, but use the magnet as
> a downforce, that should be good enough to make a sufficient contact with
> the metal plates on the chessboard!
>
> But I also thought about a combination of the IR/RFID method.
> Use coils under the chessboard to provide enough output power to supply a
> resonant coil in each figure. This resonant coil powers a timer circuit
> that pulses an IR diode with an individual fequency for each piece.
> Then put some reciver diodes under each square and read the signals with
> your PIC (all squares one by one).
> This is a more complex and more expensive method than the resistors, but I
> think it is still easier (and may be cheaper) done than the real RFID
> stuff, because there you have to give the output signal on the reciver coil
> (and of course recive the output signal with the powering coil under the
> chessboard). With the combined IR/RFID method you can safe a whole lot of
> development and calibrating time, I think!
>
> MfG,
>
> Do.Pe.
>

Well, you could even (much cheaper and easier) replace the coils with the
metal contacts. In this application the contact resistance doesn't play a too
big role, as long as the power is sufficient to drive the frequency
generating circuit in the figure.

MfG,

Do.Pe.

--
http://www.piclist.com#nomail Going offline? Don't AutoReply us!
email listserv@mitvma.mit.edu with SET PICList DIGEST in the body