Parallel Cards

A computer is a horribly complex piece of equipment, lots of pieces, some big, some small, but all important.  To make matters worse is the folks who make the computers all get together and make up the rules on how computers should operate.

So what does this have to do with CNC?

Nothing and everything.  A few years ago every parallel port/card on the planet worked at the 5 volt level.  This was “the good old days” as 5 volts is considered a TTL High and the parallel port could be easily connected to any other device and everything worked great.  But somewhere between then and now, “they” got together again and started lowering the voltage for the parallel port.  Currently I believe the spec is 3.3 volts (don’t quote me on this) and I’ve seen it as low as 2.4 volts.

Back to CNC

The problem is CNC devices need some decent voltages.  A Gecko for example requires a 5V signal to work properly and most popular breakout boards require at least 3 volts.  Without the proper voltage you get erratic operation, no operation, or just flat out flakiness.

The Solution

First of all, we had to find a 5 Volt card as for the most part we don’t use a breakout board, so our search for a good card took a little longer than it might have if we used a breakout board.  (We have not found one that works good enough for us without a makeshift do-dad to fix up the board.  But we are working on one that will work, then we will sell it with our kits)

Just to give this little tip some credibility, I was at a customers place this past weekend and low and behold nothing worked with a bran-new 4 GHZ Gateway.  After breaking out my handy dandy silly-scope and saw 2.4 volts on the port I knew the problem.  Dropped in a new card and the problem was solved.

Furthermore, when someone purchases a turn-key machine from us, we put a card or two in their PC before we ship it all back.  We don’t even test to see if it needs it.  It’s simply “part of the deal”.

Long and Short

If nothing works, but everything is right. 

It’s not acting ‘right’

It’s possessed

Or

You’re just really, really smart and want to avoid a headache to start with.

Get the card.