This was my first microprocessor: I developed assembly language for it and the 6809 using Motorola's Exorciser development system (which was already old in the mid 80s when I used it). Here is a simulator I wrote for it, in case you want to try it in Linux or Cygwin:

https://github.com/jhallen/exorsim

8 inch floppies! I remember we had an old GE chain-train printer for it which was awesome because it was so fast.