TOMAL: a high-level programming language for microprocessor process control applications

This paper describes the multi-tasking capabilities of a new microprocessor programming language that has been designed to support process control applications. A program in TOMAL is a collection of tasks, priority ordered, and possibly having real-time response constraints and internal synchronization statements. It also supports device-independent I/O programming, by allowing the characteristics of each external device to be given in a declaration. A TOMAL source program is translated into space-optimized, absolute code for a target microprocessor. The object program runs under the control of a compact, application-tailored Task Control Monitor that is also generated by the compiler. The paper discusses design philosophy and several important requirements of an implementation to achieve multi-tasking capabilities.