Introducing Hardware-in-Loop Concept to the Hardware/Software Co-design of Real-time Embedded Systems

As the need for embedded systems to interact with other systems is growing fast, we see great opportunities in introducing the hardware-in-the-loop technique to the field of hardware/software co-design of embedded systems. This technique reduces the need to develop models for existing hardware and increases the accuracy of the overall system. This work is especially important now that complexity and time-to-market constraints demand early simulation, verification, and architectural exploration of systems. We introduce the hardware-in-the loop technique to the field of hardware/software co-design of industrial embedded systems using SystemC as the modeling environment. We conceptualize the hybrid channel to clearly define the communication between real and virtual (modeled) subsystems. We patch the SystemC kernel for hard real-time execution and we improve the underlying operating system to guarantee an upper bound for the overall system latency. We have performed tests to measure the performance of our method in terms of response time and determinism. We have achieved a stable operating frequency of 10 KHz and an I/O performance of sub-millisecond round-trip time over Ethernet. Moreover we have developed a non-timed transaction-level model of a BACnet Broadcast Management Device (BBMD) and connected it with real devices to see our method´s performance in a real-life environment. Our model outperformed the competing real system up to 80 times in maximum response time. We deem the results very promising for the future of our method.