SRS Equipment and CAMAC


NIM crates and standard modules were first used in 1969. NIM, Nuclear Instrumentation Module, was popular in the nuclear and high energy physics communties. The modules were inter-changeable allowing users to build flexible experiment control systems. Modules in NIM crates were not able to communicate with one another, something that only became possible with the later CAMAC and VMEbus standards. NIM is mainly used for analogue devices.

Further information is available here.


In the 1970s all interfaces were built to the CAMAC, Computer Automated Measurement And Control standard. CAMAC was a modular system originally developed by ESONE: European Standards and Nuclear Electronics under a collaboration of several European nuclear laboratories. CAMAC modules enabled rapid design and build of integrated digital electronic control systems interfacing to an external computer.

Further information is available here.


VMEbus was developed for the Motorola 68000 CPU series from 1979. The VME crates were built using standard Eurocards plugged into a VMEbus back plane. VME crates could be equipped with a built in computer -- the Motorola MVE 167A had everything on a single board.

Further information is available here.

Other SRS Equipment

As an example, on Station 2.3 (for High Resolution Powder Diffraction and X-ray Reflectivity) a motorised diffractometer was controlled by electronic interfaces via a computer. The electronics and the computer were in the control gantry which was situated above the experimenter's hutch. The photograph shows the computer (left), the electronics rack (centre), the McLennan Drive System (right), and the TV monitors (above the PC). Two of the monitors were linked to the cameras inside the hutch and one displayed the SRS beam status.

Station 2.3 control

A new enclosure was constructed v.1996 for data analysis In the photograph, the centre computer is linked to the control computer, and it can be used to drive the diffractometer and to collect data. The SGI Indy work station on the right and the PC on the left were for data analysis. The enclosure also had TV monitors which were linked to the cameras inside the hutch and to the SRS.

Station 2.3 PCs

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