standard features if the GPIO board? Or is it just optional circuits?
That about covers it, but you need to read the links on the sidebar to get more details. With that set of functions, there is a lot that could be accomplished, For example, for transmission control, see: http://www.msgpio.com/manuals/mshift/index.html
I don't need megashift or dbw or other advanced stuff I just want some extra inputs and outputs.
I'm looking at this chematics from this link: http://www.msgpio.com/manuals/gpi.htm, for Voltage sensitive input.
Is the resistor Ra and capasitor Ca/Cb included in the kit? I cannot find the values either.
The values depend on what you are trying to do with the circuit.
- Omit Ca. Cb is purely for noise filtering. The spec is 0.1 to 1.0 uF, and Cb can also be left out completely if the signal is reasonably smooth.
- for the voltage sensing circuit, Ra merely limits any possible current to the processor pin (there would normally be very little current anyhow). For that purpose, 1K Ohms is fine.