The first clean run said both scans were fine, which conflicts with scan 473 being classified as having the artefact. Two gaps explain how that verdict could be wrong. **The file was never checked against the intended scan.** Measured fast-axis travel implies roughly 6.2 um per point in S00473 and 9.2 um in S00254, while the scans were run at 0.65 um and 1.00 um -- both about 9.3x larger. Until that is resolved the analysis rests on an unverified assumption about which axis is which and in what units. The check now prints the fast and slow axis ranges, the per-line slow step, and the implied step size, so the file can be compared directly against the scan command. A mismatch means the wrong axis, the wrong units, or motion that was not commanded, and all three matter more than anything downstream. **Whole-line spans cannot see a partial stall.** An axis that freezes part-way through a line and then continues still covers its full range, so the span test passes. Since the report describes intermittent motion loss rather than whole lines going missing, that is the more likely shape of the fault. Lines are now also scanned for runs of consecutive position samples that did not advance, reported with the same start/middle/end distribution. Verified against a file whose stalls leave every span intact: the span test sees nothing, the new one finds all eight and places them in the final tenth. Note the sampling limit still applies -- 74 position samples against 428 data points in S00473, and about 8 against 205 in S00254. A stall shorter than the sampling interval remains invisible, so a clean result here is not proof. Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
cSAXS BEC
cSAXS specific plugins and configs for BEC This document guides you through the procedure to spin up BEC at the beamline for a new experiment (e-account). You might want to run cSAXS copy scripts before in case you want to have the former data structure to be preserved.
Overview
- Clone cSAXS BEC repository into e-account (e.g. into ~/Data10/software/.)
- Start Epics iocs
- Start BEC, BEC server and load/modify the device config with relevant hardware
- BEC commands
Clone cSAXS BEC repository
Clone the current cSAXS BEC repository from GIT into the new e-account. Create directory
mkdir ~/Data10/software
cd ~/Data10/software
Clone repository
git clone https://gitlab.psi.ch/bec/csaxs_bec.git
Start epics iocs
You can start up the iocs while the ./setup_bec.sh script is running. Be aware though that the scripts requires you to interact with it.
DelayGenerator
Open a new tab in a terminal in comp1/comp2 or cons1 and follow the commands below:
ssh gac-x12sa@localhost
cd ~/delaygen
iocsh -7.0.6 startup.script
Be aware -7.0.6 is referring to the current epics version and might change in future (SLS 2.0). To start the epics panel (only if needed), run in a new shell
caqtdm -noMsg -macro P=delaygen:,R=DG1: srsDG645.ui
More notes on usages and cabelling of DDGs. Currently 3 generators are used:
- DDG1 for detectors (EXT Enable from SGalil stages, T0 to DDG2, AB for eiger, CD for Falcon, EF for Pilatus_2)
- DDG2 for mcs card (ext. enable from DDG1, AB to mcs card)
- DDG3 for fast shutter and mcs enable (AB short pulse to enable MCS (needed!!), CD to keep FSH open )
Eiger
Open a new tab in a terminal in comp1/comp2 or cons1 and follow the commands below:
ssh gac-x12sa@localhost
cd ~/Software/Eiger/
./launch_ioc
A live view of status and images for std_daq can be found here xbl-daq-29:5000.
Pilatus_2
First, start the cam server. Connect to the computer and follow the instructions printed after connecting:
ssh det@x12sa-pd-2 (Pilatus2)
The cam server will open, wait until you see **. Nex step, open a new tab in a terminal in comp1/comp2 or cons1 and follow the commands below:
ssh gac-x12sa@localhost
cd ~/Software/Pilatus300K/
./launch_epics
FalconX1
Open a new tab in a terminal in comp1/comp2 or cons1 (logged in as the current e-account) and follow the commands:
ssh x12sa-cons-01
cd /ioc/X12SA-PC-FALCONX1/
iocsh -7.0.6 startup.script
Be aware -7.0.6 is referring to the current epics version and might change in future (SLS 2.0)
Start BEC, BEC server and load device config
Step 1 needs to have finished for continuing with these steps. What remains now is to start the bec server. Connect to pc15543 and open a new terminal to run:
cd ~/Data10/software
source bec_venv/bin/activate
bec-server start
tmux attach -t bec
Open another teminal on pc15543 and start BEC:
cd ~/Data10/software
source bec_venv/bin/activate
bec
Note: In case there is a warning after starting BEC that it was not able to import scilog, you will have to pip install scilog in the bec_venv to be able to send printouts to scilog from the command line. Within a new terminal:
cd ~/Data10/software
source bec_venv/bin/activate
pip install scilog
Device config from csaxs-bec plugins
bec.config.update_session_with_file('/sls/X12SA/data/e20639/Data10/software/csaxs-bec/bec_plugins/configs/bec_device_config_sastt.yaml')
bec.config.save_current_session('~/Data10/software/current_config.yaml')
The second command is helpful if you adjust limits of motors, which will then be stored in the config and loaded if a reload of the configuration is needed.
BEC commands
A number of commands that are useful:
To move devices that are added in the config:
umv(dev.samx, 0) #absolute
umvr(dev.samx, 0) #relative
dev.samx.wm #print motor position and limits
dev.samx.limits = [low_limit, high_limit] # To set limits, note, same lower and higher limit, e.g. [0, 0] means no limits!!
Scans:
scans.acquire(exp_time = 0.5, frames_per_trigger=10, readout_time=3e-3) # equivalent to a loopscan 30 0.5
scans.line_scan(dev.samx, -1, 1, steps=20, exp_time=0.5, readout_time=3e-3, relative=True) # optional, add frames_per_trigger =10 for burst acquisition at each step
#Scan 2 motors in a step scan at the same time
scans.line_scan(dev.samx, -1, 1, dev.samy, -1, 1, steps=20, exp_time=0.5, readout_time =3e-3, relative=True) # step scan with 20 steps, again frames_per_trigger can be added for burst at each point
scans.sgalil_grid(start_y = , end_y = , interval_y = , start_x=, end_x=, interval_x =, exp_time=0.5, readout_time=3e-3, relative=True)