Hello all, I'm new to this forum. I'm building my first CNC related machine, and I hope I'll be able to learn from and contribute to this forum!

My first question is as stated in the title: What is the function of a parallel port breakout board?

As far as I can tell, the board will allow easier access to the pins, and protection for the PC in the form of isolation. However, most good quality servo/stepper drivers already seem to come with built-in opto-isolators. Having two opto-isolators seems redundant and possibly even detrimental to performance.

I have no experience using the parallel port for such controls, though I have experience with robotics, electronics and programming. Please enlighten me!

Thank you.

Hon