NODAL

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NODAL is an interpreting, higher level, interactive language especially suited for process control applications. NODAL may be executed in all three modes of operation and may call subroutines in NORD PL and MAC.[1]

NODAL (Network-Oriented Document Abstraction Language[2]) is an interpreted language implemented on Norsk Data's NORD-10 computers. Used by CERN and DESY high energy physics labs to control their accelerator hardware[3], PADAC and SEDAC. Included trackball input, graphics.[4]

NODAL allows commands to be written in one place and executed somewhere else.[5]

Basic features

NODAL is a high level language based on FOCAL and SNOBOL4, with some influence from BASIC. The language was developed to operate on the computer network controlling the SPS accelerator at CERN.

NODAL is an interpretive language designed for interactive use . This is the most important aspect of the language, and is reflected in its structure. the interactive facilities makes it possible to write, debug and modify programs much faster than with compiled based language like FORTRAN and ALGOL.

The language has three special features. The first is a syntax which supports a multi-computer network operation. The second is extensive string handling features which makes it easy to write good programs for operator interaction. The third feature is the ability to add machine code functions for specific applications. a special type of such functions is the data module. By means of data modules, process control equipment connected to the computer can be handled as program variables. NODAL also supports the international instrumentation interface CAMAC.

Sources

  1. Norsk Data Document ND–60.050.06 SINTRAN III USERS GUIDE section 1.5.1
  2. Acronym Finder - NODAL
  3. Structured design benefits to a process control software project
  4. Free Online Dictionary of Computing - NODAL
  5. How the web was born, James Gillies & Robert Cailliau, 2000, page 74, 176

The NODAL system for the SPS - 1974.

The SINTRAN III NODAL System, Oslo University Version, October 1980 (PDF).