Machine Language Subroutine Research Articles

Software for a Process-Control Laboratory

The operation of a digital computer in a control laboratory imposes stringent requirements for a suitable language. Such a machine is used as part of a hybrid computer, to control and test pilot-scale plant, to analyse pre-recorded data, and to process relevant off-line programs. To achieve this degree of flexibility a high-level language with the facility for employing machine-language subroutines is essential. For on-line systems, input and output of data involves a straight-forward extension to normal practise; the main difficulty lies in the programming for the servicing of interrupts. This paper discusses the use of Fortran as the basis language of an on-line system and compares this with possible Algol-based systems.

Symmetric list processor

A list processing system in which each list cell contains both a forward and a backward link as well as a datum is described. This system is intended for imbedding in higher level languages capable of calling functions and subroutines coded in machine language. The presentation is in the form of FORTRAN programs depending on only a limited set of “primitive” machine language subroutines which are also defined. Finally, a set of field, particularly character, manipulation primitives are given to round out the system.