Okay
here are 2 schematics with one being from a control board we use at work (uses a Freescale chip, not AVR)
I have transfered it over for the Arduino board, but as said it has to be a factor of 5.
So, how come this other one works when there are essentially two 330K resistor in series between VDD and GND, which should give 6 to 12V on the chip pin when the switch is O/C ?
The "IN 0-7" connector goes straight to the chip pin
CN8 connect to the outside world. Input is ON the switched to GND
VDD is 12-24VDC
K
