Utkarsh Sinha

If you’re into robotics, you know how important a parallel or a serial port is for computer controlled robots. And its really irritating if your computer doesn’t have either. You then need to borrow desktops from others. And that really takes up a lot of time – you install all libraries on the new computer, make sure it is positioned in the perfect manner, and a lot of other things.

This month, we were determined to find a way to use our own computers for robotics.

Initial ideas were to write drivers for the *chinese* USB-To-Parallel convertor. Not a really great idea unless you’ve written a lot of drivers before hand.

Then came the idea of using a *chinese* USB to serial, and a *chinese* serial to parallel convertor. These two components alone would have cost us around Rs. 1,000. Not a really feasible idea.

Say no to *chinese* (daupheeeeeeen style)

And then suddenly we get the idea of *making* our own USB to parallel/serial convertor using a microcontroller.

We’ve got a lot of microcontroller boards from Cypress, (based on their PSoC “microcontrollers”). So we borrowed a board with USB support. To be able to use the driver, one has to install a USBUART driver that creates a virtual serial port and essentialy feeds data from this virtual port into the physical USB port. This data then reaches the microcontroller and you can do whatever you want.

What we did was convert this value into a binary number and output these bits into four different pins. A one implies the pin in ON, otherwise its OFF. This is very similar to a parallel port. You can feed this input directly to some H-bridge (like L293D, L298, etc) or (as in our case) into a wireless transmitter circuit.

As of now, we’re working on further miniaturing our USB-To-Parallel convertor into a compact chip that you just plug into your computer, and you get a parallel port!