The MainWindow

The MainWindow is the graphical user interface for the MuPix-telescope and shown in Figure 6.5. In the version developed so far, many debug features are implemented. To perform the actual readout, only the "User friendly Testbeam Control and ReadOut" is needed. In the following, all buttons and their functions are introduced:

Top Menu Bar

• FPGA: Option bar to display the memory and register windows, which are used to check the memory or write register values by hand.

• DACs: Opens the windows for the chip and board DACs, where the values can be changed for each sensor.

• Hitmaps: This option displays the hitmaps of the 4 sensor layers.

Resets

• Reset Event Counter: This button resets the event counter that can be used as an offline crosscheck in the data stream.

• Global Reset: Sets all FPGA register values to their default values.

• Reset Hitmap: Sets the hitmaps to zero in the separate hitmap window.

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Figure6.5: Schematic view of the MainWindow.

DACs

This block is used to set the global DAC values for the four sensors, described in Section 5.4. The values of all DACs are displayed in the separate DAC windows, accessible over the Top Bar.

Readout

This block is the central one of the main window. One can choose between Read Once, Readout ContinuouslyandTriggered Readout:

• Read Once: This option activates a single readout. All sensors are read out once.

• Read Continuously: This option activates a continuous readout. In this case the FPGA reads out its two sensors continuously.

• Triggered Readout: This option would trigger a single readout after a trigger is activated. This readout mode is not used, because neither an external trigger system was available, nor needed.

70 Chapter6 DataAcquisition Hit Generator

This module can be used to generate hits on the FPGA and read them out directly in order to test the performance of the DAQ system. One can choose between a single event creation with a selectable number of hits or a continuous event generation at selectable time intervals and hits. This generator can be used to debug the software without using real sensors. This has the advantage of removing all issues concerning the sensor itself. This makes it easier to detect software issues.

Injections

The Injection 1 and 2 can be used to inject signals to the chip simulating hits. Due to the chip design, Injection 1 addresses the odd double columns and Injection 2 the even double columns. The buttonsTOP FRONT, TOP BACK, BOTTOM BACKandBOTTOM FRONTinject the signals into the different telescope layers with the strength and length set in the white input fields above. TheinjectAllbutton can be used to inject the charge pulse of both injections to all four layers.

Save Events

The save events block is used to control the file writing mode: One can select by marking thewrite events to file check box if the data taken with the telescope should be written to a file. In the white line in the center, the file-path and name can be set.

The run number displays the current run number. This function is only activated if test data is taken. For actual testbeam measurements the initial filename is hard coded and only a run number counts up to prevent accidental changes.

Thresholds

This block is used to get direct access to the global thresholds of the 4 sensors. Theload defaultbutton loads the initial values, stored in the interface and displays them in the 4 input fields. With these fields, the values can be adjusted and set with the buttons left to the fields.

Message Display

The white area in the bottom left is used for displaying different messages, like errors during readout, run changes or DAC value changes. It also displays changes in the thread IDs, occurring wrong data structures and file changes.

Chapter6 DataAcquisition 71 User friendly Testbeam Control and ReadOut

This block is the central readout scheme for the use at testbeams. The Get Ready button initializes the readout by setting all DAC values, and resetting the absolute time counter.

TheStart Runbutton starts all threads and activates the readout register for the FPGAs.

After clicking, the label changes toStop Runand clicking causes the stop of all threads and deactivates the FPGA readout. The threads are started before the FPGA starts reading out and the FPGA readout is stopped before the threads are stopped. This makes sure that all data taken are processed.

The RUN NUMBERdisplay shows the current run number.

The other outputs in the bottom half of the block display the number of hits, frames and trigger blocks read and processed. The difference of "read" and "processed" should stay constant and at low numbers. Otherwise the DAQ system is too slow and the PC runs out of memory.

TS Control

The time stamp (TS) control is used to define the time stamp frequency and enables or disables them. Thedivision factor and the correspondingTS binsize are displayed and can be changed with the slider. The time stamp is an 8bit Gray encoded counter running with a maximal frequency of 400 MHz, resulting in a minimal bin size of 2.5 ns. It can be divided by 2ⁿ withnbeing smaller than 16 resulting in minimal frequency of roughly 6 kHz corresponding to 164 µs.

This block is not editable while the readout is activated.

Non-Grouped Icons

• synch test: Test icon to check whether the system is still running synchronously.

The coarse counters of both FPGAs are displayed after clicking this icon.

• setTiming: Sets the default timing values again. This is included in the automatic readout.

• INJECT SYNCHED: Drives the injection signals from both FPGAs at the same time, which is not the case if one clicks on the other injection buttons.

• PIXEL 15/15: Not used for the telescope, can be used to debug the setup using the MuPix 4.

• DrawHitmap: Draw the hitmaps in the hitmap window.

• Reset and set default: Resets the settings and sets the default values again.

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• Exit: Closes the GUI.