Knock Sensors

I know this has come up several times, but it seems there's some information out there now that I'm hoping someone can share. I know the Megasquirt is capable of using knock sensors, but the factory knock sensors on the gen 3 Hemis are a little weird by some standards. They're not the typical 1 wire style "microphones" that a lot of the GM ones are. However, I noticed that the EFI Source MS3 Gold kit comes with knock sensor inputs and someone mentioned on a recent thread about Drag Week that they had knock control on their setup. How is this system set up? Does it use the factory sensors or do you use a simpler 1 wire style? Is there extra circuitry built into the computer or is it handled entirely with code?

It would be awesome if EFI Source would divuldge some of the info on this setup if possible. I'd really like to utilize my sensors since I already have them, but I've been a little stumped at how to incorporate them into my system. I've looked at some external filtering circuitry and understand effectively what it's doing, but I can't figure out if my sensors are working to begin with.