Ptolemy II 8.0 includes a substantial rework of modal models and the underlying finite state machine infrastructure to make them work predictably and consistently across domains.
Ptolemy II 8.0 includes a new implementation of continuous-time models based on the semantics given in "Synchronous Language Principles for Heterogeneous Modeling and Design of Embedded Systems." In particular, the Continuous domain cleanly supports continuous-time models (using an ODE solver), discrete-event models, and arbitrary mixtures of the two, including signals that combine continuous-time segments with discrete events. It also interoperates cleanly with most other domains (pretty much all except PN and Rendezvous, for which there does not appear to be reasonable semantic model of such an interaction). Modal models are also cleanly supported with the Continuous domain, enabling hybrid system modeling with a rigorous semantics. The Continuous domain is expected to eventually replace CT.