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Our first large area detector (2Mpx, 5kHz). Total data volume 2Mpx*5kHz*2bytes/px=20GB/s. 5 tiles in each quad. Each tile is 4 asics. Each ASICs is 144*192*4 (4 is number of asics).
Some slides from Matt describing how to run epixHR prototype in MFX with LCLS-I timing: https://docs.google.com/presentation/d/1gauhczW2oMYa72_jbCMgenUQj7HGwxyCLvFPvMVpK84/edit?usp=sharing
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The v2 ASIC requires descrambling of the data and the matrix readback does not work. The v4 ASIC should correct these issues.
Beam Test Trigger Setup
Detector tests run in the MFX beam line with hard x-ray beam from the LCLS NC accelerator. Thus, the 120 Hz beam is aligned with particular phases of the 60Hz AC power line, and the time between beam pulses varies with the power line sampling. In order to emulate high rate run triggers but still achieve alignment with the beam, an event code generating sequence is run in the XPM that restarts a train of triggers each 120 Hz cycle. For example, to simulate a trigger rate of 5 kHz, 41 triggers are generated with 200 us spacing every 120 Hz cycle (thus, 4920 kHz). The LCLS NC timing event codes provide enough time (~834us) to fire a few of these triggers before the beam arrives. The sequence would then generate new event codes at the following time intervals after receiving event code 40 from the accelerator:
| event code | name | description | usec after EC 40 |
|---|---|---|---|
| 0 | run trigger | used by detector to latch beam response | 34, 234, 434, 634, 834, ..., 8034 |
| 1 | daq trigger | used to readout detector | 834 + subset of run trigger |
| 2 | parent trigger | used to trigger daq parent group | 0 + all daq trigger |
| 3 | target | marks the daq event in-time with beam | 834 |
The XPM is programmed using the seq_epixhr script. It's usage is:
(ps-4.6.3) bash-4.2$ seq_epixhr -h
usage: seq_epixhr [-h] [--rate RATE] [--tgt TGT] [--daq DAQ] [--full] [--f360] [--minAC MINAC] [--pv PV] [--test] [--plot] [--verbose]
Sequence for EpixHR DAQ/Run triggering
optional arguments:
-h, --help show this help message and exit
--rate RATE Run trigger rate (Hz)
--tgt TGT DAQ trigger time (sec)
--daq DAQ DAQ trigger at RUN trigger rate/N
--full DAQ trigger at RUN trigger rate (same as --daq 1)
--f360 DAQ trigger at 360 Hz
--minAC MINAC Minimum 120H interval in 119MHz clocks
--pv PV XPM pv base
--test Calculate only
--plot Plot sequence
--verbose Verbose
The pv argument programs the sequence to a particular engine within the XPM, thus assuming the event codes that appear. Lastly, the a readout group must be driven by the run trigger event code. Since the DAQ makes no use of this readout group, it has to be done manually with groupca.
Running devGui
From Alex Batyuk:
| Code Block |
|---|
cd /cds/home/w/weaver/epix-hr-new/software
source ./setup_l2si.sh
python scripts/ePixHr10kTDaqLCLSII.py --start_viewer True --start_gui True |
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