Transcript HADES slow control - GSI

Control System Requirements
for the CBM detector
Burkhard Kolb
GSI HADES
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
CBM Requirements
• CBM is a complex detector system with more
than 100000 parameters
• It has all the usual controls as HV, gas, power,
temperature etc.
• Many of the FE components will be custom
build and require loading of FPGA or CPLD
designs
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
CBM Requirements
• FE and trigger electronics require thresholds
and tuning parameters
• FE and trigger electronics require monitoring of
status and performance.
• All loadable parameter sets/ design files will
come from version controlled records of SQL
database
• Access to parameters with security control
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
CBM Requirements
• Scalability
– Start with detector prototypes
– Run the full DCS with no loss of performance
• Partitioning
– Independent testing of sub systems
– Development in outside labs
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
CBM Requirements
• Alarm handling
• Interlock monitoring
• Archiving to SQL database
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
CBM Requirements
• No dependence on proprietary tools, protocols,
hardware and software, except on custom chip
and board level for front ends
• Long time range of operation and maintenance
• Interoperability with existing control systems to
allow flexible inclusion of sub systems
• Open standards
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
HADES will become a part of the CBM
detector and has now an EPICS control system
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
Geometry
Six sectors form a hexagonal frustum:
• 2p in f
• 18 < J < 85
Lepton Identification
•
RICH
– Radiator: C4F10
– Spherical mirror
– Photon Detector: CsI photo cathode
•
META
– TOF plastic scintillators
– Lead PreShower detector
Tracking
•
Superconducting toroid (6 coils)
– Bmax = 0.7 T,
– Bending power 0.34 Tm
•
MDC (multiwire drift chamber)
– Low mass design
– four planes of small cell (» 1 cm) drift chamber.
In total about 100.000 detector channels
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
HADES trigger scheme
6
10 evt. / s
1st level trigger
 106 s-1 interact. rate (1 % target)
• LVL1 trigger : multiplicity (TOF)
META
Multiplicity
o Central collision:
5
10 events/s
delay ~ 100ns
o all detectors read out (3 Gbyte/sec)
o storage in pipeline memory (< 32 evts.)
2nd level trigger
RICH
META
Rings
Showers
105 s-1
•
LVL2 trigger: Ring & Shower search in
RICH & META
o Lepton candidates:
Matching
103 s-1
o transfer of data to next pipeline memory
3
o track info to 3LVL processor
10 events/s
delay ~ 100µs
•
3rd level trigger
MDC
Tracks
2
10 evt. / s
delay: 10 ms
LVL3 trigger: MDC & LVL2 info
o Not yet implemented as we can write with 40
Mbytes/s to disk
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
Status
• EPICS is installed:
– EPICS base on Linux, WinNT, and MAC OS X
– Some EPICS extensions
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MEDM (Motif editor and display manager)
ALH (alarm handler)
Burt (backup and restore)
Channel Archiver
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
EPICS applications
• VME crate, CAMAC crate, and MDC power
supply control, RICH LV control (CANbus)
• LeCroy 1440 HV control (CAMAC)
• Dubna HV control (serial)
• CAEN 527 HV control (VME - CAENnet)
• Position monitors (RASNIK + portable channel
access server (CAS))
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
EPICS applications
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Gas bottle scales readout (serial)
CFD control (CAMAC)
Temperature sensors (via sockets)
General purpose ADCs (VME)
TOF laser and filter control (VME)
Start detector discriminator & veto logic (VME)
Accelerator parameters (CAS on VMS)
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
EPICS applications
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MDC drift time monitor (LabView CA server)
MDC oxygen monitor (VME)
MDC gas pressure
Spill start
Scalers for start, veto and trigger detectors
RICH gas monitor
RICH HV trip sequencer
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
EPICS security
• Security is now enabled on an (UNIX) account
basis
• All read parameters are visible to everybody
• All set parameters are owned by accounts
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
Experience with EPICS
• As with all complex systems the learning curve
is quite steep at the beginning.
• It proved to be very helpful to copy an existing
example application.
• Addition of new hardware and drivers is quite
easy, but requires moderate C experience
• Configuration of record database and GUI is
easy.
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
Experience with EPICS
• Connection to LabView works well
• 1 to 2 persons is sufficient to build up and
maintain the installation
• Integration of a SQL database is a complex task
and requires agents on host machines.
• No version management of parameter sets
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
EPICS overview
• Tool Based:
– EPICS provides a number of tools for creating a control system. This minimizes
the need for custom coding and helps ensure uniform operator interfaces.
• Distributed:
– An arbitrary number of IOCs and OPIs can be supported. As long as the network
is not saturated, no single bottle neck is present. A distributed system scales
nicely. If a single IOC becomes saturated, it's functions can be spread over
several IOCs. Rather than running all applications on a single host, the
applications can be spread over many OPIs.
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
EPICS overview
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
EPICS overview
• OPI
– Operator Interface. This is a UNIX based workstation which can run various
EPICS tools (WinNT too).
• IOC
– Input Output Controller. This is VME/VXI based chassis containing a Motorola
68xxx processor, various I/O modules, and VME modules that provide access to
other I/O buses such as GPIB.
• LAN
– Local area network. This is the communication network which allows the IOCs
and OPIs to communicate. EPICS provides a software component, Channel
Access, which provides network transparent communication between a Channel
Access client and an arbitrary number of Channel Access servers.
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
EPICS overview
• DATABASE:
– The memory resident database plus associated data structures.
• Database Access:
– Database access routines. With the exception of record and device support, all
access to the database is via the database access routines.
• Scanners:
– The mechanism for deciding when records should be processed.
• Record Support:
– Each record type has an associated set of record support routines.
• Device Support:
– Each record type has one or more sets of device support routines.
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003
EPICS overview
• Device Drivers:
– Device drivers access external devices. A driver may have an associated driver
interrupt routine.
• Channel Access:
– The interface between the external world and the IOC. It provides a network
independent interface to database access.
• Monitors:
– Database monitors are invoked when database field values change.
• Sequencer
– A finite state machine.
Control Systems for Future Experiments @ GSI, May 12 - 13, 2003