Author: Beetham, C.G.
Paper Title Page
S08NC05 The Transmission of Accelerator Timing Information around CERN 306
 
  • C.G. Beetham, K. Kohler, C.R.C.B. Parker, J.-B. Ribes
    CERN, Geneva, Switzerland
 
  Prior to the construction of the Large Electron Positron (LEP) collider, machine timing information was transmitted around CERN’s accelerators using a labyrinth of dedicated copper wires. However, at an early stage in the design of the LEP control system, it was decided to use an integrated communication system based on Time Division Multiplex (TDM) techniques. Therefore it was considered appropriate to use this facility to transmit timing information over long distances. This note describes the overall system, with emphasis placed on the connectivity requirements for the CCITTG.703 series of recommendations. In addition the methods used for error detection and correction, and also for redundancy, are described. The cost implications of using such a TDM based system are also analyzed. Finally the performance and reliability obtained by using this approach are discussed.  
DOI • reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S08NC05  
About • Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992  
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S10TS05 A New VME Timing Module: TG8 360
 
  • C.G. Beetham, G. Daems, J.H. Lewis, B. Puccio
    CERN, Meyrin, Switzerland
 
  The two accelerator divisions of CERN, namely PS and SL, are defining a new common control system based on PC, VME and Workstations. This has provided an opportunity to review both central timing systems and to come up with common solutions. The result was, amongst others, the design of a unique timing module, called TG8. The TG8 is a multipurpose VME module, which receives messages distributed over a timing network. These messages include timing information, clock plus calendar and telegrams instructing the CERN accelerators on the characteristics of the next beam to be produced. The TG8 compares incoming messages with up to 256 programmed actions. An action consists of two parts, a trigger which matches an incoming message and what to do when the match occurs. The latter part may optionally create an output pulse on one of the eight output channels and/or a bus interrupt, both with programmable delay and telegram conditioning.  
DOI • reference for this paper ※ doi:10.18429/JACoW-ICALEPCS1991-S10TS05  
About • Received ※ 11 November 1991 — Accepted ※ 20 November 1991 — Issued ※ 04 December 1992  
Cite • reference for this paper using ※ BibTeX, ※ LaTeX, ※ Text/Word, ※ RIS, ※ EndNote (xml)