In case you're involved in developing for the Atari ST, you may find my curated list of dev resources handy. If you have any useful links i can add, please let me know or create an issue in the repository! https://github.com/sandord/atarist-dev-resources
maxYMiser — an Atari ST YM2149 chip tracker.

maxYMiser is the best and most up to date chip tracker for the Atari ST, and is still under constant development.

@mmu_man Thanks!