Mousing Around

Since my Tandy 1000SX had high resolution graphics (if you could call monochrome CGA 640x200 high resolution) we thought it made sense to get a mouse and learn to program with it. Then we might be able to write even better software for the engineers to use when setting up each circuitboard for production. We had a crude graphical CNC simulator that ran on the Kaypro machines, so this could be a step forward for us with more detailed graphics and a mouse for a pointing device.

We bought the mouse at Radio Shack. It was a pretty nice little mouse, and it came with its own interface card like most mice did back then. I'm guessing that this mouse was made by the same people who made the the famous Microsoft Mouse. It was very similar. All the mice at that time had a ball for tracking movement, and this one was a metal ball with a rubber coating.

I believe that my first experiments with the mouse were in Turbo BASIC. There were no built in commands for the mouse. I don't remember exactly how the mouse was read either, but I remember there was documentation. Playing around with some code for drawing on the screen with the mouse inspired me to write an experimental character recognizer. I would draw letters on the screen and the program would attempt to convert them to ASCII characters. It really wasn't that hard to do, but prototypes don't have to be practical. It was fun.

Paper Tape

When there was a mistake in a long CNC program, sometimes it was easy to tell that it was a mistake at the beginning of the program. Rather than read the whole thing in, edit it in WordStar and then punch a whole new tape, sometimes it was easier to repair the paper tape itself.

Usually you could just create a new section of paper tape, and then you unroll the tape to the section you are looking for and splice in the change. With some practice it wasn't too hard to read the binary numbers by eye. Instead of ASCII values, CNC programs were punched to tape using EIA (Electronic Industries Association) codes.

In some instances if you didn't need to change the number of characters, but just which values (change some digits for example), you could just cover the holes with tape and punch new holes. I think I did that at least a couple of times.

So, this all seems very archaic right? On the plus side you really had control over the stored data. Today if your disk drive or your flash memory loses a bit you can't even see it let alone fix it. ;-)