ASSIST (the Assembler System for Student Instruction and Systems Teaching) is an
IBM
International Business Machines Corporation (using the trademark IBM), nicknamed Big Blue, is an American Multinational corporation, multinational technology company headquartered in Armonk, New York, and present in over 175 countries. It is ...
System/370
The IBM System/370 (S/370) is a range of IBM mainframe computers announced as the successors to the IBM System/360, System/360 family on June 30, 1970. The series mostly maintains backward compatibility with the S/360, allowing an easy migrati ...
-compatible
assembler and
interpreter
Interpreting is translation from a spoken or signed language into another language, usually in real time to facilitate live communication. It is distinguished from the translation of a written text, which can be more deliberative and make use o ...
developed in the early 1970s at
Penn State University
The Pennsylvania State University (Penn State or PSU) is a Public university, public Commonwealth System of Higher Education, state-related Land-grant university, land-grant research university with campuses and facilities throughout Pennsyl ...
by Graham Campbell and
John Mashey along with student assistants.
In the late 1960s, computer science education expanded rapidly and university computer centers were faced with a large growth in usage by students, whose needs sometimes differed from professionals in batch processing environments. They needed to run short programs on decks of
Punched cards
A punched card (also punch card or punched-card) is a stiff paper-based medium used to store digital information via the presence or absence of holes in predefined positions. Developed over the 18th to 20th centuries, punched cards were wide ...
with fast turnaround (minutes, not overnight) as their programs more often included syntax errors. Once they compiled, they would often fault quickly, so optimization and flexibility were far less important than low overhead.
WATFIV was a successful pioneering effort to build a
FORTRAN compiler tuned for student use. Universities began running it in a dedicated "fast-batch" memory partition with a small run-time limit, such as 5 seconds on an
IBM System/360 Model 67
IBM mainframes are large computer systems produced by IBM since 1952. During the 1960s and 1970s, IBM dominated the computer market with the 7000 series and the later System/360, followed by the System/370. Current mainframe computers in IBM' ...
). The low limit enabled fast turnaround and avoided waste of time by programs stuck in infinite loops.
WATFIV's success helped inspire development of ASSIST,
PL/C and other student-oriented programs that fit the "fast-batch" model that became widely used among universities.
ASSIST was enhanced and promoted by others, such as
Northern Illinois University
Northern Illinois University (NIU) is a public research university in DeKalb, Illinois, United States. It was founded as "Northern Illinois State Normal School" in 1895 by Illinois Governor John P. Altgeld, initially to provide the state with c ...
's Wilson Singletary &
Ross Overbeek and
University of Tennessee's Charles Hughes and Charles Pfleeger who reported in 1978 that ASSIST was being used in 200+ universities.
In the 1980s, NIU did a new implementation on IBM PCs, ASSIST/I (Interactive), used by computer scientist John Ehrman to teach a "boot camp" course in assembly programming at
SHARE (computing)
SHARE Inc. is a volunteer-run user group for IBM mainframe computers that was founded in 1955 by Los Angeles-area users of the IBM 704 computer system. It evolved into a forum for exchanging technical information about programming languages, opera ...
meetings, at least through 2011, but perhaps for several years after.
On March 1, 1998, Penn State declared that ASSIST was no longer
copyright
A copyright is a type of intellectual property that gives its owner the exclusive legal right to copy, distribute, adapt, display, and perform a creative work, usually for a limited time. The creative work may be in a literary, artistic, ...
ed and that the
program was
freely available as per the last release notes.
The original ASSIST code seems to still get some use, as seen in 2017 demonstration video assembling its source and running it in
MVS 3.8 emulation on a laptop.
IBM System/360 and /370 computers used
24-bit
Notable 24-bit machines include the CDC 924 – a 24-bit version of the CDC 1604, CDC lower 3000 series, SDS 930 and SDS 940, the ICT 1900 series, the Elliott 4100 series, and the Datacraft minicomputers/ Harris H series.
The term SWORD ...
addressing and ignored the high-order 8 bits. Assembly programmers of the era, including those who wrote ASSIST, often saved precious memory by using the high-order 8 bits for flags, which required a compatibility mode when IBM introduced
31-bit and then
64-bit
In computer architecture, 64-bit integers, memory addresses, or other data units are those that are 64 bits wide. Also, 64-bit central processing units (CPU) and arithmetic logic units (ALU) are those that are based on processor registers, a ...
addressing.
References
External links
ASSIST Introductory Assembler User's ManualASSIST - Assembler System for Student Instruction & Systems Teaching (IBM System /370 Reference Summary)Assist distribution archivemaintained by NIU's Michael Stack
{{DEFAULTSORT:Assist (Computing)
Interpreters (computing)
IBM mainframe software