In my FV-1 designs so far, I've used an SPDT ON-ON switch to select between two presets. However, a lot of pedal manufacturers seem to get three presets using a SPDT ON-OFF-ON switch, and I simply can't seem to figure out how they're doing it. Do I not actually need to ground the pins for them to be in the 0 position?
This is exactly how I do it. The cool thing is that you can use a SPDT On-On switch when you only need two modes, or On-Off-On when you need three. No further circuit modifications needed.