Automated synthesis of microprogrammed control units in DIADES

Presents the automatic synthesis of microprogrammed control units in the DIADES design automation system. The optimization of the microcode is incorporated into a comprehensive process of data path scheduling and allocation and of control unit design. A new microprogrammed controller model that is suitable for design automation and formal description is described. This new model permits design and optimization of controllers ranging from a very basic microcontroller to a very complex one. The micro-sequencer architecture is retargetable. A symbolic intermediate microcode (SIMC) is generated as a high-level intermediate microassembly language. In SIMC, some high-level control constructs from the behavioral input language ADL of DIADES and GRAPH88 are preserved and can either be implemented in hardware or converted into lower-level microinstructions. An object-oriented HyperCard-based user interface has been designed to simplify user access to the system