The Cambell Design BOB+ looks like an excellent piece of kit, but I'm really tempted to "save" myself approximately $115 in startup costs by buying a disposable $15 PCI parallel port for now. Will an add-in parallel port card serve as a sacrificial barrier or is my PC still likely to fry if I should accidentally wire something incorrectly?
BTW I know the BOB+ offers more than just optoisolation, but in an effort to keep costs down on my CNC project, I'm trying to avoid adding on all of the bells and whistles out there.
TIA