What's going wrong in my SIOC code?

[dnoize]

Maria,

the optical encoders (CTS288 type, like OC sell) have three pins and you should look on them like follows :

Just to rule out any confusion: these encoders are NOT optical !!

Other than that totally correct. you just beat me to the post Peter

Stef

[pdpo]

Stef,

your right ... those are not optical...

concerning the pots, also the USB expansion card allows 4 analogue inputs.
same there, you got three pins, the outers are connected on each side of the
resistor film and the middle pin is connected to the slider.
So in order to connect to the usb expansion, just connect the two outer pins (GND and +5V)
to the outer pins of the potmeter and the middle pin connect to the slider.
If you swap the two outer pins of the potmeter you will get the effect that the resistance will swap. To be sure the pin connections of a potmeter you better test them out with a multimeter. Between the two outer pins you should measure the full resistance of the potmeter which does not change when turning the slider.
Some potmeters also provide more then three pins and here you need to chek for sure because some of those have 2 pins which are direct connected to eachother and if you would connect those two pins to the 2 outer pins ( 5V and GND) on the card then you would create a short circuit which might damage the card.

Greetz Peter