We present a rigorous formal - but transparent - specification of the semantics of a generic simulation-based 3D animation framework. Our system combines a SystemC simulation kernel with a virtual visualization machine for 3D animation. The semantics of the simulator and the virtual visualization machine are formally defined by means of ted Abstract State Machine (ASMs) rules. The ASM rules truly reflect the specification given in the SystemC User's Manual and additionally provide a comprehensive definition of the virtual machine for advanced 3D animation. For the interaction between the SystemC simulator and the visualization we have defined a simple message exchange protocol, which can be used for socket communication. We see our formal semantics as a concise, unambiguous, high