I've lately become hooked into building computers in Minecraft and today I decided to build a giant hard drive. I've built HDDs before, but not at the scale I'm currently attempting, and I anticipated problems. As I was wiring some pistons, they activated and pushed forward oddly. As far as I can tell, there's nothing powering them.
Here's a top view of the same pistons. I also thought the line of redstone above them might be the problem (middle of above pic), but when I destroy it, the pistons stay extended.
Is there a reason why my pistons are extending? If so, is there a way to get them to power (when I want them to) without disturbing the pistons above?
Here's a side view of the HDD, in case it's something else: