Triggering a Hardware Project with a Parallel Port

Mike Szczys of Hack A Day wrote in with this guide to hacking parallel ports on old computers.

It turns out it’s super easy to use the parallel port (most likely hasn’t been used for years IF your machine has one) to trigger external electronic projects. I’m using an NPN transistor to use pin 1 of the parallel port as if it were a button connected to my ATtiny13.