Going Retro

Today I decided I wanted to try and see if I could resurrect a program from about 30 years ago. I had (still do but don’t know if works) a Vic-20. It was my first computer. I typed a lot of programs into it from books and magazines and wrote programs myself. Early on I had no storage. It was type in the program, debug it, run it and then reset the computer and poof all that work was gone. My parent’s got a datasette. This was a specialized cassette recorded that plugged into the Vic-20. I could now save things. Eventually I was able to write programs with custom graphics.  I searched for and found the cassette with the programs on it. Then I found a working cassette player, third try. I then captured the audio signal to a laptop.

Example wave pattern of data on cassette for a Vic-20

This is how the data was stored digital in analog format. If you listen to the audio it sounds like a modem. First I tried to convert the signal directly. The utility I found would only work in older PCs. Eventually I wound up trying to run it in FreeDos in VirtualBox. The problem was I could not figure out how to get the input audio into the FreeDos. I then decided to just record the data to a wav file. Two utilities later I settled for WAV-PRG. This can take a wav file and convert it into TAP or PRG files. Armed with both these files I then tried to load the programs into the VICE emulator. I would run the load command several different ways and could not get it to work. But tomorrow is another day. I will have to go back and try to record a different tape, one without the custom graphics. So I know what I will be doing tomorrow.