Flashing Driver Station Digital Input

[EricVanWyk]

Your current set up either connects the pin to ground or it doesn't. I meant to set it up so it connects to ground or power.

Not all switches can do this. As a quick check, if it has 3 pins it probably can. The technical term is "double pole", meaning that it has two inputs it can toggle between.

As for the pullup method:
I like 10kOhms, but there is nothing magic about this number. You want it to be high enough that you are not drawing too much power through it, but low enough so that it does its job.
Take what ever you have laying around, make sure it is between 1k and 100k and give it a shot. You could probably get away with higher or lower, but I wouldn't bother with it.

EDIT: For reference, the digital side car uses 10kOhms on all of its GPIO pins and 3.17k on its I2C pins. We needed a stronger (lower resistance) pull up on the I2C so it could pull hard enough to hit the maximum data rate. Since you are probably working at human data rate (SLOW), you can get away with a lot of slop.