Kronos processors family for high level languahes
Dmitry Kuznetsov, Alexey Nedorya, Eugene Tarassov, Vladimir Philippov, Marina Philippova
The KRONOS processors family was developed in the SB AS USSR Computing Center within the framework of the MARS project (Modulnye Asinkhronnye Razvivayemye Sistemy – Modular Asynchronous Developable Systems) in the period of 1983-1990.
The goal was to create a multi-purpose processor with hardware support of high-level languages for constructing open-architecture computers: from embedded microcomputers and single-processor workstations to multiprocessor workstations of the super-mini class. Presented below is the overview of the processors’ architecture and the operating system for them.
KRONOS is the generic name for the family of 32-bit processors for creating micro- and mini-computers. The KRONOS processor architecture was oriented towards the support of high-level programming languages (C, Modula-2, Pascal, Occam, etc.) which allowed to implement the newest ideas in computer usage. Modula-2 was chosen to be used as the basic development language.
The project authors used creation experience of Lilith computer carried out under the guidance of N. Wirth in the ETH, Zurich; however, many of the decisions were made quite independently. For instance, while the sets of RAM value access commands, arithmetical and logical operations and control structures remained all but unaltered, there were substantial changes in the architectures of process interaction, interruptions, addressing and working with peripheral devices. Many simplifications were achieved thanks to the 32-bit processor.
32-bit machine word made it possible to use processors of the family for solving computational problems. The wide address space (up to 4 billion words) gave the possibility to create virtual memory for object-oriented computation models, thus enabling the development of AI systems.
The hardware support of event interruption and process synchronization together with the compactness of program code guaranteed the successful application of KRONOS processors in real-time systems.
The KRONOS processor family included three products: 2.2, 2.5, and 2.6. Computers with Kronos 2.2, Kronos 2.5, and Kronos 2.6 processors worked under the Excelsior operating system designed for solving a wide range of tasks.
The Kronos 2.6 WS workstations were used by a number of military industry companies. An example of notably fruitful and long-term cooperation was the joint project with M. F. Reshetnev NPO PM (Nauchno-Proizvodstvennoye Obyedineniye Prikladnoi Mekhaniki, Applied Mechanics Research and Production Group) in Krasnoyarsk-26. In October, 2005 an operational Kronos 2.6 worksta