Cyber-Physical Systems pair discrete-event computational components with physical components that are governed by continuous-time dynamics. If we are able to simultaneously model the computational and physical aspects of a system, then we could drastically shorten timelines for such systems by being able to simulate, evaluate, and formally verify integrated system behavior all prior to the costly phase of deployment. In this work, we present the Signal Flow Domain Specific Modeling Language: a free and open language for describing synchronous control logic within the Cyber-Physical Systems Modeling Language (CyPhyML). Signal Flow is adept at modeling software processes, and its functional blocks are math functions which reference underlying C-code snippets. Furthermore, Signal Flow models can synthesize deployable C-code, for use within the target hardware platform. We describe the use of Signal Flow within CyPhyML for integrating the computational and physical components of a bidirectional DC/DC converter intended for use in a hybrid vehicle. We first derive the circuit behavior, and then model the full system in CyPhyML employing Signal Flow to model the vehicle controller.