Design of reactive PIC microcontroller

Reactive embedded applications require fast reaction to external events (defined as reactivity in this paper). Esterel is a system-level language for the modeling, verification and synthesis of reactive systems through high-level support for efficient interaction with environment, synchronous communication and concurrency. Existing compilers for Esterel compile it to intermediate C code, which preserves Esterel semantics, before generating machine code that runs on a specified processor. Hence, the resultant code is often huge and inefficient, even for very small programs, as the underlying processors have no direct support for reactivity needed to execute Esterel. This paper proposes, for the first time, a reactive microcontroller called RePIC (which is an extension of the commercial PIC microprocessor). RePIC supports direct Esterel execution through a reactive instruction set architecture (ISA), while preserving Esterel semantics.