A control and sequencing language

Abstract

In a process control environment, hatch processes, as opposed to continuous processes, are characterised by multi-product manufacturing lines which often involve frequent product changes. One component of batch control systems is a programming language which is used to control and synchronise the operations of the plant. Initially low-level languages (e.g. ladder logic, boolean algebra and assembly language) were used, but have now been replaced by specialised high-level languages. These languages provide more functionality and are easier to use. The dissertation examines one such high-level sequencing language (CASL) and identifies functionality, clarity and readability improvements that can be made to the language. An implementation of an upwardly compatible compiler for the improved language is described briefly.