I had one as my first computer, used it for years.
Tape recorder to load a few bought games, and managed to write a basic program to play Mastermind (working out colour of 4 hidden coloured pegs).
Poke &HFFD7,0 - this used to "up clock" it, this would run some programs quicker, but not all. It also made the cursor faster.
This was 40 years ago, and I still remember &HFFD7,0 …. but no idea what I did this morning, how is that?
Richard