"YUL System - Pass 0"

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Hugh Blair-Smith
MIT Instrumentation Lab (Apollo, Shuttle).


The YUL System had to play several roles in the development of AGC software. Aside from fulfilling its original requirement, to be an "assembler for an unknown number of machines with unknown characteristics," it had to serve as a program editor, version control system, and "manufacturer" of binary program images on punched mylar tape. The assembly occupied Pass 1 and Pass 2, manufacturing occupied Pass 3, and so-called Pass 0 was the entry point to all functions from the "Monitor," which was MIT/IL's multi-tasking OS for the Honeywell 800/1800. Pass 0 did the version control and editing at the card-image level. This listing is the Pass 0 source in "MITIGUS" (MIT/IL's dialect of Honeywell's ARGUS assembly language).


Presented in Session G: "Digital Engineering and Computer Design: A Retrospective and Lessons Learned for Today's Engineers"

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