Interface for CNCPro, etc.

> Suppose I design a card that will fit in one ISA or PCI slot that
> has optoisolation, 5V isolated supply for outputs and a screw
> terminal strip that sticks out the back for direct connection to
> amps, switches and aux I/O. No interface cards to make, no pullup
> resisters to find a home for, no breakout boards to buy, no 25 pin
> DIN connectors or cut-to-length serial cables to fiddle with. Just
> connect the amps, switches and I/O to the back of the PC and go.

Put a high quality bulkhead connector in the card edge guide, like a
db50 with screw attachments. Put 3 foot of wire between the bulkhead
and the screw terminals so you can work on it without moving the PC.

| we are rapidly approaching the day where a commodity PC costs less
| than specialized I/O or interface boards. Perhaps the computer
| should be considered expendable? I mean, go ahead and gain whatever
| degree of protection is cheap and easy, but it's not worth spending
| a couple hundred bucks on limited production hardware to protect a
| couple hundred bucks worth of mass produced computer.

Don't forget to count time lost to unreliability from partially zapped
hardware. It's hard to tell when something's only weakened, not dead.

Brian