Technical Reports (CIS)

Document Type

Technical Report

Date of this Version

May 1982


University of Pennsylvania Department of Computer and Information Science Technical Report No. MS-CIS-82-145.


Nopal is a descriptive non-procedural very high level language for writing specifications of programs for test of analog and digital electronic circuits by Automatic Test Systems (ATS). It can also be used for writing specifications of general purpose computation. Based on a NOPAL specification, the NOPAL processor generates a computer program in the ATLAS test language. A specification in NOPAL may consist of a number of modules,one of which is the main module. The main module consists of a collection of specifications of individual tests given non-procedurally in an arbiitrary order. A test in NOPAL corresponds to the notion of a physical test a unit under test (UUT). A test consists of stimuli (signals) to be applied measurements to be taken and logic for selecting diagnoses depending on the passing or failing of one or more tests. Information about the UUT and automatic test equipment (ATE) may also be included in the main module. The UUT and ATE information is used for conducting various consistency checks and is included in the produced documentation. A module, other than the main module, specify functions which apply stimuli, make measurements or evaluate variables. Interfaces among modules are provided by referencing in one module function specified in another module. The NOPAL processor analyzes the specification of module for consistency, completeness and non-ambiguity and generate error/warning messages and a number of reports which serve as the documentation for the specification. If the specification is error free, the NOPAL processor orders the program events to attain efficiency in computer time and in use of memory. Finally, it generates a program in the EQUATE-ATLAS Test Programing Language. ATLAS programs, generated from modules of a specification, are submitted together for compilation and executed on RCA EQUATE AN-USM-410 computer controlled ATE.


automatic testing, atlas, analog testing, digital testing, nonprocedural languages, very high level languages



Date Posted: 19 November 2007