1. Control and Monitoring of Front-end and Readout Electronics in ALICE Peter Chochula

2. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Outline Front-End and ReadOut electronics (FERO) access strategy will be described using SPD as an example Front-End and ReadOut electronics (FERO) access strategy will be described using SPD as an example Live demonstration of a prototype solution Live demonstration of a prototype solution Discussion of related problems Discussion of related problems This is not a first presentation on FERO problematics. Proposed solution should now be adopted as ALICE standard – your feedback is therefore essential.

3. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Basic Interaction Between FERO and DCS FERO controls ranges from downloading of parameters to high-level tasks such as calibration FERO controls ranges from downloading of parameters to high-level tasks such as calibration Monitoring includes direct reading of parameters provided by the electronics or indirect surveillance using associated equipment (power supplies etc.) Monitoring includes direct reading of parameters provided by the electronics or indirect surveillance using associated equipment (power supplies etc.) Corrective actions are expected from the control system in case of anomalous values (errors, excessive readings etc.) Corrective actions are expected from the control system in case of anomalous values (errors, excessive readings etc.)

4. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva The Front-end Device (FED) The FED makes implementation details transparent to higher software layers The FED makes implementation details transparent to higher software layers FED encapsulates hardware and software into a unit FED encapsulates hardware and software into a unit Accepting standard and detector specific commands Accepting standard and detector specific commands Publishing standard and detector specific data Publishing standard and detector specific data

5. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva FERO FERO configuration is implemented via DDL FERO configuration is implemented via DDL Monitoring is based on different technologies Monitoring is based on different technologies DDL ConfigurationMonitoring Class A ConfigurationMonitoring FERO FERO configuration can be performed via DDL and optionally using alternative techno- logy (Profibus, Ethernet, etc.) FERO configuration can be performed via DDL and optionally using alternative techno- logy (Profibus, Ethernet, etc.) DDL Class B Non-DDL technology FERO Control and Monitoring Strategies in ALICE ConfigurationMonitoring FERO alternative technology such as Profibus, Ethernet, Easynet etc. is used to configure FERO alternative technology such as Profibus, Ethernet, Easynet etc. is used to configure FERO Class C Non-DDL technology ConfigurationMonitoring FERO Configuration and Monitoring are sharing the same access path to FERO Configuration and Monitoring are sharing the same access path to FERO Class D Four different FERO architecture classes should be transparent to upper software layersFour different FERO architecture classes should be transparent to upper software layers FERO should be treated as any other device:FERO should be treated as any other device: accept commands accept commands publish status and gathered data publish status and gathered data

6. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Class A+B Control The Front-end Device (FED) DAQ/RCDCS Control CPU FERO Hardware Layer FED Server FED Client Profibus, JTAG, etc. Control CPU DDL SW FED DDL Monitoring of all classes Communication based on DIM

7. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Class B,C,D Control Class A+B Control The Front-end Device (FED) DAQ/RCDCS Control CPU FERO Hardware Layer FED Server FED Client Profibus, JTAG, etc. Control CPU DDL SW FED DDL Monitoring of all classes

8. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Class B,C,D Control Class A+B Control The Front-end Device (FED) ECS DAQ/RCDCS Control CPU FERO Hardware Layer FED Server FED Client Profibus, JTAG, etc. Control CPU DDL SW FED DDL Monitoring of all classes

9. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva SPD Readout Architecture DC S Trig DAQ JTAG, CLK, Detector Data ~100m PCI-MXI-II-VME VME Router Card 1 router services 6 halfstaves SPD contains 20 routers

10. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva ALICE SPD as an example for FED Implementation Basic SPD block seen by online systems is a half stave Laser and Pin Diodes GOL - Translates data into G-Link compatible 800Mbit/s stream and drives the optical laser component Digital Pilot –receives trigger signals, controls chips, reads analog pilot Analog Pilot – provides reference voltages, ADCs for monitoring ALICE1/LHCB Chip – reads signals from bump-bonded pixel sensors MCM

11. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva SPD Operation Modes Configuration Mode: JTAG Bus is used to configure ALICE1 chips Monitoring of MCM is suspended Operation Mode: ALICE1 chips are taking data JTAG Bus is reconfigured and services only the MCM MCM is monitored via JTAG JTAG

12. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Monitoring of ALICE SPD Monitoring Commands Data (Temp,I,V,flags)

13. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Configuration of ALICE SPD New Configuration Data Current Configuration Data CONFIGURING ! New Configuration Data Old Data Output

14. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Implementation of SPD FERO Control Application called “SPD FED Server “ written in C++ (WXP) Application called “SPD FED Server “ written in C++ (WXP) Various tasks implemented as threads Various tasks implemented as threads Configuration Configuration Monitoring Monitoring Readout tests, etc… Readout tests, etc… Operation of threads is synchronized by the main application Operation of threads is synchronized by the main application The threads are called AGENTS The threads are called AGENTS

15. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva SPD Agents Monitoring Agent (MA) Control Agent (CA) Monitoring Agent continuously reads the MCM parameters During the execution of control task the operation of MA must be suspended The MA is allowed to resume its operation SPD FED SERVER

16. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Architecture of SPD Control and Monitoring Software (PVSS) DIM Client CA1 CA2MA1 SPD Halfstave MCM Router VISA PCI-MXI-VME Database DIM server Data Monitoring Agents (MA) are implemented as separate threads Control Agents (CA) react to commands received by the server Monitoring Agents (MA) publish data as DIM services FED Server Client Software Commands

17. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Generic architecture of the FED software (PVSS) DIM Client CA1 CA2MA1 Hardware Device driver(s) Database DIM server Data DIM Interface allows for communication with higher levels of software Hardware access layer contains device drivers FED Server Client Software Commands Application layer contains detector control and monitoring code (agents)

18. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva SPD FED Server SPD FED Server is one and only access point to the hardware SPD FED Server is one and only access point to the hardware FED server accepts commands and executes them FED server accepts commands and executes them It arbitrates access to the hardware It arbitrates access to the hardware Synchronizes internal execution of agents Synchronizes internal execution of agents Main (DCS) role of the server is monitoring of sensitive detector parameters Main (DCS) role of the server is monitoring of sensitive detector parameters Acquired data is published as service Acquired data is published as service

19. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva FED Server commands and services The communication can be divided into standard and sub-detector specific parts. The communication can be divided into standard and sub-detector specific parts. Standard commands include setup and monitoring of the FED servers itself, initialization and actions common for all architectures Standard commands include setup and monitoring of the FED servers itself, initialization and actions common for all architectures SPD specific part includes procedures used only by SPD SPD specific part includes procedures used only by SPD

20. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva DIM Interface of the SPD C/M Server Recognized commands General: General: Initialize Initialize Re-initialize Re-initialize Calibrate Calibrate Modify Running parameters Modify Running parameters Publish Active Settings Publish Active Settings SPD Specific SPD Specific Test Readout Test Readout Test JTAG Test JTAG Test SEU Test SEU Start/Stop Agents Start/Stop Agents Published services General: General: Server Status Server Status Agent Status Agent Status Messages Messages Detector data: Detector data: Temp Temp I, V I, V Status and error flags Status and error flags

21. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva FED Server operation The server needs to be first configured (there are standard built-in settings). This includes: The server needs to be first configured (there are standard built-in settings). This includes: Setting of logging method Setting of logging method Setting of readout frequencies for the agents Setting of readout frequencies for the agents Setting of deadbands for the agents Setting of deadbands for the agents On request the agents start their operation. States of individual agents are visible to all server components and are used for internal synchronization On request the agents start their operation. States of individual agents are visible to all server components and are used for internal synchronization Monitoring agents typically read data in predefined intervals (auto-triggering). External triggers are possible Monitoring agents typically read data in predefined intervals (auto-triggering). External triggers are possible

22. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva SPD Agent States Idle/Alive Executing Suspended Suspend Wakeup Execute (or auto-trigger) The agent is ready and waits for command or auto-trigger Idle agent sends heartbeat to the main thread The agent accesses the hardware and performs its task (FERO configuration, DCS data readout, etc.) The agent fully relies on main thread – during its execution all potentially interfering agents must be suspended. Status of other threads is signaled to individual agents. Execution of complex agents can be interrupted by external command (e.g. calibration run can be stopped and FERO can be reloaded) The agents are suspended at server’s startup time (to avoid interference e.g. during crash recovery when the state of bus is not known) Agents can be suspended also on request (e.g. to disable auto-triggering for a short period) On wakeup the agent automatically resumes its previous task

23. Live demonstration

24. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva FED Server Setup Debugging Level Control Server Operation Parameters Debugging Output Control Internal Agent Status Monitoring Settings The Server Setup Panel allows tuning of server operation and debugging sets monitoring limits and refresh rates controls complexity of published messages controls publishing of debugging informatio

25. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva FED Server Control Agent Status Info: Suspended Executing Idle Server Status Info: Operational Initializing Calibrating Checking JTAG ….. Server Commands The Server Control Panel allows sending commands to the FED On receipt of command C/M Server: Suspends monitoring agents (if needed) Performs requested task Resumes agent operation

26. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Messenger Service and Message Viewer Detector Caller MesageSeverity Time & Date Example of PVSSII Message Viewer (based on DIM service) Messenger Service provides information about server’s operation Complexity of published messages can be remotely tuned Message destinations: DIM based viewers Logfiles/screen Windows Event Logger (ActiveX)

27. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Detector Data Subscriber Data in this panel is updated according to server settings (frequency,deadbands, etc..) PVSSII is the main DCS operation tool PVSS client subscribes to data published by the C/M server Gathered data is treated according to DCS recipes

28. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Automatic evaluation of communication status Server operational but no data published Connection to Server lost! OK

29. End of demonstration

30. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Optional DIM clients Although PVSSII is the main DCS operation tool, it is not required to have it running in order to monitor data provided by the C/M Server Although PVSSII is the main DCS operation tool, it is not required to have it running in order to monitor data provided by the C/M Server Additional clients such as Custom C++ clients, DimTree or DID can connect to C/M server in parallel to PVSS client Additional clients such as Custom C++ clients, DimTree or DID can connect to C/M server in parallel to PVSS client Operation of custom clients presents a serious risk to the DCS and their use will be strictly forbidden during running. The usage of extra clients will be allowed only for monitoring purposes. Operation of custom clients presents a serious risk to the DCS and their use will be strictly forbidden during running. The usage of extra clients will be allowed only for monitoring purposes.

31. Live demonstration of optional DIM clients

32. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Integration of FED with DCS FED can be described in terms of state machines and integrated with DCS using SMI++ interface FED can be described in terms of state machines and integrated with DCS using SMI++ interface The aim is to identify common operational aspects and set them as ALICE standard. The aim is to identify common operational aspects and set them as ALICE standard. Each detector will use its additional specific states Each detector will use its additional specific states

33. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Modelling the FED as a FSM : standard part READY RUNNING STANDBY Go STDBY Initialize Initializing Re-Initialize RunStop

34. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Modelling the FED as a FSM : sub-detector specific (the READY state is taken from precious example) Calibrating READY Checking SEU Checking JTAG Checking R/O Check SEU Check JTAG Calibrate Check Readout

35. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Applications of described approach outside the FERO Domain In principle the described concept can be used to access any equipment requiring remote supervision C/M DIM VISA Stepper Motor Controller C/M DIM VISA RS-232 Non-standard Power Supply RS-232 or Ethernet Mirrors adjustable by stepper motors

36. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Partial Conclusions Described model allows for monitoring and control of non-standard devices in ALICE – not only FERO Described model allows for monitoring and control of non-standard devices in ALICE – not only FERO The FERO is treated as a device. The developed software makes all hardware details transparent to higher software layers The FERO is treated as a device. The developed software makes all hardware details transparent to higher software layers We need your feedback in order to be able to standardize the commands We need your feedback in order to be able to standardize the commands

37. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva A working FED server is just the beginning of the story… Implementation of FERO software is a very complicated task requiring a lot of expertise – however it is still the easier part Implementation of FERO software is a very complicated task requiring a lot of expertise – however it is still the easier part Tuning of the software will require much more time and experience Tuning of the software will require much more time and experience DCS team is happy to discuss and help at least to transfer the knowledge between different groups. (Maybe someone already solved a problem which you are dealing with…) DCS team is happy to discuss and help at least to transfer the knowledge between different groups. (Maybe someone already solved a problem which you are dealing with…)

38. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Configuration Errors Wrong Configuration Data Non-working chip

39. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva What is the source of erroneous data? Wrong configuration record in database Wrong configuration record in database Wrong configuration version retrieved from database Wrong configuration version retrieved from database Data transmission errors Data transmission errors interference with DAQ, TRG, crosstalk, … interference with DAQ, TRG, crosstalk, … single event effects … single event effects … Software errors Software errors Interference between monitoring and control Interference between monitoring and control Interference between control tasks Interference between control tasks Interference between several clients – PVSS should be the ONLY client allowed to send commands to FED Server Interference between several clients – PVSS should be the ONLY client allowed to send commands to FED Server

40. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Communication between online systems and sub-systems There are many cases when online systems need to be synchronized – in fact this is probably the most complicated FERO related problem There are many cases when online systems need to be synchronized – in fact this is probably the most complicated FERO related problem Procedures depend on hardware architecture as well as on detector operational modes Procedures depend on hardware architecture as well as on detector operational modes Spotting of problems and implementation of correct procedures requires close collaboration between different specialists Spotting of problems and implementation of correct procedures requires close collaboration between different specialists The first step is to understand the operation of the sub- detector and then analyze consequences for each case The first step is to understand the operation of the sub- detector and then analyze consequences for each case

41. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva … just a few examples Some operations require additional actions: Some operations require additional actions: Power sequence might temporary lead to a very high power consumption – software interlock levels must be raised until the situation stabilizes (e.g. until FERO initialization). In addition a RESET must be sent to FERO and some dummy configuration loaded, so an action on LV triggers an action on FERO as well. Power sequence might temporary lead to a very high power consumption – software interlock levels must be raised until the situation stabilizes (e.g. until FERO initialization). In addition a RESET must be sent to FERO and some dummy configuration loaded, so an action on LV triggers an action on FERO as well. Additional action from other systems might be necessary: Additional action from other systems might be necessary: (Re-)Initialization might require stopping of trigger (downloading of data sometimes introduces unwanted noise, running DAQ sequence might corrupt currently downloaded data) (Re-)Initialization might require stopping of trigger (downloading of data sometimes introduces unwanted noise, running DAQ sequence might corrupt currently downloaded data)

42. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva … just a few examples Typical initialization sequence is not a single-step procedure and can be even split between several systems: Typical initialization sequence is not a single-step procedure and can be even split between several systems: DCS must assure the power and cooling are present DCS must assure the power and cooling are present DCS related circuitry will be loaded and checked DCS related circuitry will be loaded and checked Only now the DAQ can proceed with configuration Only now the DAQ can proceed with configuration Additional adjustments and checks performed by DCS might be needed Additional adjustments and checks performed by DCS might be needed

43. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva … few more examples DCS can detect and correct problems which are not immediately visible to other online systems. DCS can detect and correct problems which are not immediately visible to other online systems. Problems in DCS sub-system can affect other online system Problems in DCS sub-system can affect other online system In some cases DAQ and TRG will be asked to perform additional actions In some cases DAQ and TRG will be asked to perform additional actions On following slide we use a generic “CLASS A” front-end to demonstrate the problem

44. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Typical problem requiring synchronization between online systems DCSDAQTRG FEROVR ECS VR Failure (e.g. due to SEU) Recovery Action by DCS FERO lost its Configuration DCS informs the DAQ and TRG via ECS DAQ reloads the FERO

45. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Propagation of hardware related problems Problems can propagate between sub-systems and affect different parts of the detector: Problems can propagate between sub-systems and affect different parts of the detector: E.g. recovery of a VR failure could lead to corruption of configuration in neighboring sector (spikes, etc.). E.g. recovery of a VR failure could lead to corruption of configuration in neighboring sector (spikes, etc.). Such problems can remain hidden (e.g. change in threshold settings) and will be discovered only by offline Such problems can remain hidden (e.g. change in threshold settings) and will be discovered only by offline If we are aware of potential problems we could maybe use a simple procedure to correct them before they badly affect the data If we are aware of potential problems we could maybe use a simple procedure to correct them before they badly affect the data

46. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Things to be understood In principle every single chip can be acessed individually. Allowing for such access would lead to complications for some architectures In principle every single chip can be acessed individually. Allowing for such access would lead to complications for some architectures Example: rather than creating a service for each individual temperature sensor we could create groups for sub-detector modules and publish all data together Example: rather than creating a service for each individual temperature sensor we could create groups for sub-detector modules and publish all data together This requires balancing between number of services and update rates (we should not update a service with 1000 values if only one value changes, but we also do not want to have 1000 individual services instead) This requires balancing between number of services and update rates (we should not update a service with 1000 values if only one value changes, but we also do not want to have 1000 individual services instead) Partitioning of sub-detectors should be done very carefully (taking into account both control and monitoring aspects) Partitioning of sub-detectors should be done very carefully (taking into account both control and monitoring aspects)

47. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva A few more things to be understood What should be the structure of DIM commands? What should be the structure of DIM commands? Command structure should include the target and data to be transferred. Command structure should include the target and data to be transferred. Should we define standards for payload or set weak rules? The segmentation and naming differs between sub-detectors, definition of common standard would not be intuitive and therefore will lead to errors. Should we define standards for payload or set weak rules? The segmentation and naming differs between sub-detectors, definition of common standard would not be intuitive and therefore will lead to errors. It is essential to create a naming convention for each detector and understand its segmentation in terms of control, DAQ readout and monitoring. It is essential to create a naming convention for each detector and understand its segmentation in terms of control, DAQ readout and monitoring.

48. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva Still some question marks What is the amount of data to be exchanged between DCS and FERO and at what frequencies? What is the amount of data to be exchanged between DCS and FERO and at what frequencies? What is the structure of this data What is the structure of this data Example: temperatures for given sector can be sent as an array containing values for each probe. Another approach would be to send data structure containing only values which have changed and decode this information in PVSSII Example: temperatures for given sector can be sent as an array containing values for each probe. Another approach would be to send data structure containing only values which have changed and decode this information in PVSSII

49. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva …yet another one What should be the granularity of agents? What should be the granularity of agents? Should we set common deadbands for all values acquired by the individual agent? (e.g. update temperature readings if any of them changes by more that 0.5C) – PVSSII will of course provide another level of filtering of these values Should we set common deadbands for all values acquired by the individual agent? (e.g. update temperature readings if any of them changes by more that 0.5C) – PVSSII will of course provide another level of filtering of these values Should be the deadbands set more precise? (e.g. allowing for masking of faulty sensor at the level of FED server) Should be the deadbands set more precise? (e.g. allowing for masking of faulty sensor at the level of FED server) All answers depend on individual architectures. All answers depend on individual architectures.

50. Peter Chochula – ALICE DCS DCS Workshop – March 2004, Geneva How to proceed? Working and stable FED server is the starting point. It can be developed in advance – using emulators in the hardware access layer Working and stable FED server is the starting point. It can be developed in advance – using emulators in the hardware access layer Once the hardware arrives, one could fully concentrate on operational aspects. New procedures will be discoverred with time and can be implemented in software Once the hardware arrives, one could fully concentrate on operational aspects. New procedures will be discoverred with time and can be implemented in software Communication with other sub-detectors is essential. DCS team is happy to assist you in this point. Communication with other sub-detectors is essential. DCS team is happy to assist you in this point.