CERN Timing Overview

1. CERN Timing Overview CERN timing overview and our future plans with White Rabbit Jean-Claude BAU – CERN – 22 March 2012

2. Sequencingmodels • Goal • Strong coupling concept • Loose coupling concept • Interaction Loose/Strong coupling • Timing distribution • Messages sent on the timing network • Local timing • Client timing libraries • Future of the CERN timing • Overall view • First White Rabbit implementation Overview

3. Sequencing Sequencingmodels Main goal

4. Cycle Extraction Extraction Injection Injections time Cycle 1 Cycle 2 SequencingmodelsStrongcoupling concepts

5. Basic Period Extraction Injections time Cycle 2 BP 2 BP 1 Cycle length = N * Basic Period Basic Periodlength = currently 1200ms SequencingmodelsStrongcoupling concepts

6. Injections Beam Client Acc time Cycle 3 Extractions Inj. Acc. time Cycle 1 Cycle 2 All cycles are linked together : All cycles of a beam are always played SequencingmodelsStrongcoupling concepts

7. Spare beams time Client Acc Beam A Beam B Beam C Beam D Beam E Inj. Acc. time Beam A Beam A A spare must be on the shadow of its parent Beam B Beam C Beam D Beam F SequencingmodelsStrongcoupling concepts

8. Beam Coordination Diagram A B C Client Acc D E F H time Phase Duration A A B B C Inj. Acc. F G D E I time Duration A BCD is executed in a loop Each accelerator has its own phase All accelerators in a BCD have the same duration SequencingmodelsStrongcoupling concepts

9. Sequence Sequence 3 Seq. selector Sequence 2 Loop waiting condition Loop waiting condition Executed 1 time Executed 1 time Normal Operation Coast Prepare Coast Coast Recover Output BCD SequencingmodelsStrongcoupling concepts

10. Coupling/Decoupling Manual Decoupled acc. play different BCDs & seq. No beam can be played Can be recoupled at some key points Sequence 1 Acc 1 Sequence 2 Acc 2 Automatic Coupling point Decoupling point Acc 1 Normal Operation Coast Prepare Coast Coast Recover Acc 2 SequencingmodelsStrongcoupling concepts

11. Advantages • Manage by one timing data master • Optimize the usage of the accelerators • Constraints • Maintenance • Complex • Find a common basic period of time SequencingmodelsStrongcoupling concepts

12. When to apply this model ? • Frequent beam transfer among accelerators • Short cycle length • Optimization of the accelerators • Very close accelerator schedule (maintenance) • Use at CERN for LEIR, BOOSTER, CPS , SPS SequencingmodelsStrongcoupling concepts

13. Loose coupling Unpredictable time Collisions Filling Inj. Inj. time • Used when : • The duration of the cycle is unpredictable • The cycling time of the accelerator is long compared to its injector • Need to be synchronized with injector only at injection points (RDV) • Need to wait the injector at the RDV point SequencingmodelsLoosecoupling concepts

14. LHC Injection LHC injectors Data Master (Strong coupling) LHC Data Master (Loose coupling) Beam request (Type, Ring, Nb batches, ….) Unpredictable time Predictable time Forewarning Injection Injection Sequencingmodels Interaction Loose/Strongcouplingaccelerators time time

15. Timing network Timing Data Master Triggers • Used to trigger • Local counters • Real Time tasks • High priority messages External triggers • Describe the played Cycle and the next one • Particle type, beam destination, … • Sent every Basic Periods • Low priority messages Telegram • Identification of the timing cable • Auto configuration of the computer • Low priority messages Cable id • UTC time for time stamping • Low priority messages UTC time • To check the quality of the transmissions • Low priority messages Diagnostics Distributed timing Messages sent on the timing network

16. Time window UTC millisecond ticks Msg 1 Msg 2 Msg n Time t0+1ms t0 RT Task Msg 1 Messages sent on the timing network Msg 2 Distributed timingMessages sent on the timing network

17. Timing Receiver card Timing network Msg 1 Msg 2 Msg n Clocks External starts • Trigger external devices • Chain counters among timing receivers Pulses RT Task Distributed timing Local timing

18. Complex timing layout Distributed timing Local timing

19. Front-end timing libraries DB Applications (FESA, …) Concept of triggers/fields Timing abstract layer Transformation Timing low level layer GMT specific WR specific Concept of triggers/payloads/Telegram To be defined WR Receiver GMT Receiver Distributed timing Client timing libraries White Rabbit network GMT network

20. Overview • http://www.ohwr.org/attachments/913/wrCernControlAndTiming.v1.1.pdf • Complex to manage redundancy for Timing & Data • WRDM with two ports for the redundancy Future of the CERN timingOverallview

21. VLANs Future of the CERN timingOverallview

22. Consist of two synchronized WRDM running exactly the same thing  Produce the same messages • Only one at a time sends its messages on the WR network • The switch between the WRDM should be transparent • Main goal : • Fast upgrades during a technical stop • Reduce intervention time in case of hardware failure of the WRDM WRDM: Master/Slave Future of the CERN timingOverallview

23. WRDM: Solutions Future of the CERN timingOverallview

24. AD& ELENA decelerators Loose coupling • AD -> Renovation • ELENA -> New accelerator • Main constraints • AD injection : Can’t wait on the flat top.  synchronization at the start of the ramp • Cycle length unknown (Stop) • AD ejections to ELENA Strong coupling accelerators Stop Ej. to ELENA Inj. Future of the CERN timing First White Rabbitimplementation

25. WR deployment WRDM AD & ELENA • Deployment for end of 2013 • Only a WRDM, No WR nodes foreseen • WR to GMT gateway (end 2012) • Use of GMT receivers • Deployment for end of 2014 • AD in production, ELENA in commissioning  2 WRDM ? • Deployment for end of 2015 • Both in production WR/GMT Gateway GTM Receivers GTM Receivers GTM Receivers GTM Receivers Future of the CERN timing First White Rabbitimplementation

26. Thank you for your attention