Just made the first release (0.30) of Nonpareil, a multi-architecture calculator microcode-level simulator evolved from CASMSIM. In addition to the HP Classic series (HP-35, HP-45, HP-55, and HP-80), it now implements the HP Woodstock architecture, initially supporting the HP-25.
Generalizing the code to handle multiple architectures was somewhat more work than I originally expected. The display interface is still not sufficiently general; for instance, it can’t easily support the HP-41C family, which is currently simulated by my NSIM simulator. Since I want to merge that into Nonpareil, I’ll have to think up a cleaner interface.