What exactly does a USB to Parallel Port cable do?

[TSTwizby]

I'm looking to do data transfer from a device I'm designing to and from a computer, in the short term for personal use, but hopefully something that can be made more portable later on. USB seems the obvious way to go for this, but while the data from the device is fine in analogue, the data to it would be much simpler to deal with if it were digital. Analogue-to-Digital conversion is typically expensive, but I've found a few USB to Parallel Port cables lying around which, if they work in an intuitive way, might be just as effective for what I'm trying to do.

Specifically, I have a bunch of motors and a bunch of slide pots on the device, and the position of the slide pots needs to be sent back to the computer while the computer just tells the motors to turn on or off. If anyone has any other suggestions to make, or solutions I may have overlooked, please let me know.

 

[Wall Street]

This sounds like something that would be easier with an Arduino board...

 

[TSTwizby]

Easier, but more expensive. In the short term that's fine, but in the long term I'd like to explore other options.

 

[corkyg]

As I recall (from the depths of years ago) the USB to parallel cable was only good for printers. Somewhere I recall it had to do with timing.

 

[freeskier93]

A parallel port is still digital communication. There's no way around it, if you want it to talk to the computer you need an ADC. There's a reason why things like Arduino's exist, they make life infinitely easier. They are also cheap.

 

[dave_the_nerd]

Microcenter had chinese knockoff Arduino Uno R3s for $10 when I was there today. (Official Arduinos are made in Europe somewhere.)

The USB-Parallel adapter I use with my old CD printer was $30.

Your call, OP.

 

[piasabird]

Printer cables tend to be expensive. Of course you could just get a printer that uses USB by default. That would make finding a cable a lot cheaper. They send both data and signals back and forth.

Printers have buffers or memory. So some process has to take place that tells your computer to send more data to print or when the buffer is full or empty. The computer can probably just do this in the background using DMA Memory. So the printer has to send signals to the computer through the printer driver telling when to send more data or when to stop sending. The printer driver probably already knows the buffer size and sends just enough data to fill the buffer.