Hartran and Fortran on Atlas

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The papers in this section are mainly provided by Brian Chapman.

A large part of the anticipated workload for Atlas was expected to come from Harwell and the Rutherford Laboratory. Both organisations had made use of IBM computers both at Aldermaston and Risley. In consequence, a large body of programs already existed written in Fortran. Getting a Fortran system up and running as soon as Atlas arrived was essential. The only way to ensure that at the time was to write a compiler and loading system for Atlas (called Hartran) that would be available as soon as the machine arrived.

Ian Pyle of Harwell was in charge of the team working on the project with Bart Fossey and Barbara Stokoe, who both moved to the Atlas Computer Laboratory, being heavily involved.

The Hartran loading system was made available on the Atlas II at Aldermaston using a modified version of the S2 Fortran compiler (S3) originally developed for the IBM 7030 (Stretch).

This system was then made available on the Cambridge Titan. Cambridge also produced a Fortran compiler called T3 aimed at compiling student jobs.

Barbara Stokoe, Jack Howlett, Bart Fossey: 1965

Barbara Stokoe, Jack Howlett, Bart Fossey: 1965
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The set of people who worked on Hartran were:

Initial Project Design
Alan Curtis and Ian Pyle
BAS Specification
Alan Curtis and Ian Pyle
ASP Specification
Ian Pyle
Fortran Compiler Design
Ian Pyle
Fortran Compiler Phase 1
Ian Pyle and Barbara Stokoe
Fortran Compiler Phase 2
Brian Chapman
Fortran Compiler Phase 3
Bart Fossey and Paul Bryant
ASP Assembler
Bob McLatchie
BAS Loader
Arthur Trice
Hartran Interface
Bart Fossey

Others who did some work include Bob Hopgood (Library Routines and Debugging), Bob Conrod (assembler).

Additional information on Hartran can be found here: