Dynamic partial reconfiguration of logic controllers implemented in FPGAs

Technological progress in recent years benefits in digital circuits containing millions of logic gates with the capability for reprogramming and reconfiguring. On the one hand it provides the unprecedented computational power, but on the other hand the modelled systems are becoming increasingly complex, hierarchical and concurrent. Therefore, abstract modelling supported by the Computer Aided Design tools becomes a very important task. Even the higher consumption of the basic electronic components seems to be acceptable because chip manufacturing costs tend to fall over the time.

The paper presents a modelling approach for logic controllers (e.g., Home Area Network controllers) with the use of Unified Modelling Language (UML). The proposed method combines advantages of graphical notation (readability, convenience, intuitiveness) with the benefits of text specification languages (precision, versatility). Furthermore, the possibility of dynamic partial reconfiguration of the prototyped controller is presented.

Thanks to the Model Driven Development (MDD) approach, starting with a UML state machine model, through the construction of an intermediate Hierarchical Concurrent Finite State Machine (HCFSM) model, a collection of Verilog files is created. Adopting the MDD approach contributes a significant improvement to the hardware design process in terms of productivity, portability, interoperability and maintenance. Automating the code generation becomes easier through a better separation of concerns.

The system description generated in HDL can be synthesized and implemented in reconfigurable devices, such as FPGAs. Modular specification of the prototyped controller permits for further dynamic partial reconfiguration of the prototyped system. The idea bases on the exchanging of the functionality of the already implemented controller without stopping of the FPGA device. It means, that a part (for example a single module) of the logic controller is replaced by other version (called context), while the rest of the system is still running.

The method is illustrated by a practical example by a sample of Home Area Network (HAN) system.

Author: Grzegorz Bazydło
Conference: Title