Edinburgh Multi Access System (EMAS)

Speaker: Bob Eager
Date: Thursday 17th November 2022
Time: 14:30

25 Copthall Ave, London EC2R 7BP and
Via the Internet using ZOOM.


About the seminar

The Edinburgh Multi-Access System (EMAS) project started in 1966, and resulted in a real service to users from 1971, running on an ICL System 4/75. In 1976, work started on porting this to the ICL 2900 series, and a service was offered from October 1978. The University of Kent took up the system, and offered a service from late 1979. A further port was made to IBM and IBM clone systems, with the final service being closed in 1992.

EMAS was very efficient and reliable (arguably much more so than the manufacturer’s offerings). It was technically advanced in several ways, one example being the memory mapped file system.

The talk will cover the history of EMAS, and then look at some of the more interesting technical aspects of the system

About the speaker

I graduated in Electronics from the University of Kent in 1973, followed by a Master’s in Computer Studies at the University of Essex. I was then invited back to Kent to do research in the area of operating systems portability. In 1978 I was appointed as a lecturer, but rapidly seconded (for 50% of my time) to help evaluate the Edinburgh Multi-Access System as a replacement for the unreliable VME/K system. I oversaw it for the next eight years, with some challenging technical issues along the way. Subsequently I managed the University's VAXcluster for six years before taking ten years as Master of Darwin College. I returned to become Director of Admissions for Computing until my returement in 2015. Throughout this time I was teaching, mainly operating systems and compiling techniques.

In retirement, I have indulged my interest in historical computing, particularly in the areas of simulators and replicas. My most recent project was the resurrection of the Cambridge TRIPOS system on the PDP-11, from incomplete and internally incompatible pieces of source code. My long suffering wife allows me to keep a lot of ‘junk’ (her words) in the house, a shed, and a large storage unit.

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