Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 Electrical Tests of SCT modules using RODs Peter W Phillips Rutherford Appleton Laboratory

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 An Apology... I haven’t really thought about ROD software since early August. Moving home left a lot of catching up to do! As a consequence, this “updated” presentation is not quite as up to date as I would have liked!

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 Overview Macroassembly Testing Diagnostic Tools Future Requirements The need for a flexible approach “SCTAPI” Schedule

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 Macro Assembly Sector Test

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 Macro Assembly Sector Test - Confirmation Sequence++

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 Macro Assembly Sector Test - Confirmation Sequence++

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 Macro Assembly Sector Test - Confirmation Sequence++

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 Single Threshold Scan A single threshold scan is performed for an injected charge of 2.0fC. The input noise is estimated from the measured output noise and the known average gain of each chip, which has been shown to remain constant over periods of many hours. This is one of the fastest methods that can be used to make comparative noise measurements. Multiple L1A Studies Two L1A triggers are sent to the module, separated by a specified number of clock periods. The first event of the pair is thrown away leaving the second event to be histogrammed. By varying the spacing of the two triggers the occupancy of the modules is determined at various points during the readout cycle. In ATLAS, events will be recorded as data transmission is taking place: it is important that any electrical activity correlated with data transmission does not feed back to the front end. Diagnostic Tools

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 Repeated Noise Occupancy Here the modules are configured to a fixed threshold and repeated measurements of noise occupancy are made to monitor the stability of the system. The threshold chosen for such studies is typically 1fC, the nominal operating threshold of the ATLAS SCT. Correlated Noise Studies Data is acquired in the same manner as for a Noise Occupancy measurement, however each event is now written to a file. Analysis of the common mode component of the noise may be performed offline. “Eye” Plots used during timing adjustment Diagnostic Tools

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 Trimming Adjustment of trim settings to compensate for the effects of irradiation. Front End settings Adjustment of front end current settings to compensate for the effects of irradiation (algorithm tbc.) Other Tests The tests described here are really just examples - we’re always going to come up with new requirements, hence flexibility is important. => “SCTAPI” an interface between the user and what lies beneath Future Requirements

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 SCTAPI Operator Requirements  To be able to read in system configuration information from persistent storage.  To be able to read in module configuration and calibration information from persistent storage.  To be able to vary the parameters of a module’s registers, from the system level down to a single chip.  To configure trigger parameters  To configure BOC parameters  To configure and execute scans  To retrieve, save, analyse and display scan data  To be able to define arbitrary groupings of modules and treat them differently when changing parameters, executing scans etc.

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 SCTAPI Data modes Trigger Groups Each output datalink can receive trigger bit streams from TIM, or from the master DSP serial ports 1 and 2. We wish to be able to use these facilities to send a different type of command/trigger sequence to modules associated with each of a number of trigger groups. Data Groups Each SCT module is assigned to one of a number of Data Groups. Each data group has its own settings to define how data from its members is processed. (Ideally these groups would be arbitrary across a system of RODs, but restrictions may be imposed by the ROD architecture.)

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 SCTAPI Data modes Each data group should process the data from its assigned links according to defined accumulation algorithms including: 1. Occupancy histogram (nhits x strip, for each plane) 2. Multiplicity histogram (nevents x nhits, for each plane and for each chip separately) 3. Occupancy per event (OPE) histogram (nhits x event, for each plane and for each chip separately) 4. Fit Results Tables (params x strip, for each link)

Peter W. PhillipsATLAS SCT Week, CERN, September/October 2002 Schedules John Hill’s talk is probably a better place to start - however I have a few short comments: A working system is needed at Oxford in January - including configuration database, data archival and DCS interaction. This is somewhat more complex than the level of progress envisaged in Tom Meyer’s schedule. It may be possible to physically unite a ROD with a harness and six barrel modules before the end of the year - but this doesn’t sit well with the present software schedule.