> Here it is.
>=20
> I was mistaken about the MCU, I used the PIC16F690.
>=20
> The schematic is just for the touch circuit to save bandwidth, you are us=
ing a
> different MCU anyway.
> The function of the resistors is to give a voltage level clearly differen=
t when the
> panel is not touched. In my setup I got readings close to zero in both X =
and Y axis
> when the panel is not touched and above 300 when it is touched. I used th=
e threshold
> of 50 for testing purposes.
>=20
> The code below was trimmed just to the minimum necessary.
> The delays are too long and can be reduced a lot, some of them can be com=
pletely
> eliminated. They were introduced to try to eliminate an interference when=
 the
> equipment was used in a nightclub but were ineffective and I forgot to re=
move them.
> It seems that inside a nightclub there is a lot of RFI and the conductive=
 surfaces
> of the touch-pad are an excellent antenna.
>=20
>=20
> Best regards,
>=20
> Isaac

Excellent, thanks Isaac.

The TI appnote that I read mentioned putting ferrite beads on the wiring fr=
om the touch screen to minimise interference, along with capacitors at the =
MCU pins, although the caps will increase the settling time of the signal a=
fter the touch happens.


--=20
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--=20
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