Interrupt driven fortran for laboratory support

Abstract

This paper presents a method to increase the efficiency of general purpose minicomputer usage in a laboratory environment through subroutines to a higher level language. As an example, the implementation of a general purpose routine for the complete support of an Analog-to-Digital Subsystem is given; both from the viewpoint of the implementation in an assembly language and the usage of the corresponding FORTRAN subroutine. To extend the capability of such a system, certain non-FORTRAN attributes were included in the implementation. These extensions include the ability to use FORTRAN completion subroutines. That is, after an event or series of events has occurred, it is possible for the assembly language event processor to interrupt the execution of the main FORTRAN program and start up correctly a FORTRAN completion routine to manipulate the data as required by that application. When that task is finished, the main program will be continued from where it was suspended with no apparent side effects. This feature allows a fairly complex (but nevertheless straight-forward) FORTRAN program to control several experiments or portions of the same experiment in a completely asynchronous way.