Data Acquisition Manual for GiPS (Gamma-induced Positron Spectroscopy) Experiments

Version as of 10.02.2021 (original one from 06.02.2019)

The data acquistion set up consists of a event-synchronized readout of various digitizers in VME standard. The system is based on the Multi-Branch System developped at GSI. The continuous support of the data acquisition group at GSI, esp. Dr. Nikolaus Kurz, is gratefully acknowledged.
You are asked to type in the bold face emphasized text. As an example we assume the frontend machine to be rio4l-3 and the account eposdaq.

Starting the data acquisition from an x-terminal window:

Start the NoMachine nxclient process on any of the x-terminals or from a Windows PC and log in as user eposdaq
Open several xterm windows
Two xterm windows should be opened on the Sugarhat Linux-based operating system running on rio4l-3 (VME-card onboard computers or crate controllers from CES). The manual states: "Sugar Hat Linux 1.1 is an enhanced distribution of Open Source Linux based on the MontaVista Software’s Hard Hat Linux 2.0 distribution (Montavista Software, Inc) which provides the PowerPC Cross Development Kit (CDK) and target environment. Sugar Hat Linux 1.1 provides an interface to the CES hardware resource and a set of drivers and services that allow applications to exploit the CES RIO boards hardware features.".
We start with the process first which delivers and takes data from the accelerator by an OPC-server. The communication to the readout software is done via a shared memory segment.
Now, we may start the file output using the remote file server.

eposdaq@xbee78:>ssh -X eposdaq@fwklux5
PassWord: xxxxxxxxxxx
eposdaq@fwklux5:~$ cd bin
eposdaq@fwklux5:~/bin$ rawDispRFIO64b
-I- 64 bit RFIO server (fwklux5) listening on port 1974 forks './rawServRFIO64b' for each client request
mbs> connect rfio fwklux5 -disk
-rio4l-3 :transport :Connected RFIO server!
mbs> open file /data/fwkk/eposdaq/RPVS-.lmd size=950 -auto -disk -rfio
-rio4l-3 :transport :open file at server fwklux5::-rio4l-3 :transport :/data/fwkk/eposdaq/RPVS-0001.lmd
eposdaq@fwklux5:~/bin$:

-I- client no 1 accepted log file client no. 1: ./eposdaq.t1384492050.p22571.log

It is necessary to fully qualify the file name including the full path. Take care that the account which started t

he rawDispRFIO64b server has write permission on the directory selected.

Now, the file is open and you can start to take data. It is not necessary to stop the running DAQ and restart.

- mbs> sta acq
  -rio :util :start acquisition mbs> -rio :read_meb :found trig type 14 == start acquisition user_readout: start acquisition triggered -rio :collector:acquisition running

Now, the system is taking data and would serve them over the ethernet where data are taken by a remote event server.

The status of the acquisition can be inquired by:
mbs> show acq
-RIO4L-3:util :-------------------------------------------------------------- -RIO4L-3:util :ACQUISITION INITIALIZED 24-Jan-17 10:48:00: active tasks: -RIO4L-3:util :m_dispatch m_msg_log m_util m_read_meb m_transport -RIO4L-3:util :m_collector m_daq_rate m_stream_serv -RIO4L-3:util :SB setup LOADED from setup.usf. -RIO4L-3:util :Readout table NOT LOADED, acquisition RUNNING. -RIO4L-3:util :There are 32 streams with 32 buffers a 32768 [b] each. -RIO4L-3:util :Current crate is 0, event builder is RIO4. -RIO4L-3:util :-------------------------------------------------------------- -RIO4L-3:util :Crate 0: ID= 1, LOCAL SYNC SYNC , subevent slots=200000. -RIO4L-3:util : trig 1: cvt= 20, fclrt= 12 [usec], max se length=1000000 b -RIO4L-3:util : trig 2: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 3: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 4: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 5: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 6: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 7: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 8: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 9: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 10: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 11: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 12: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 13: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 14: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util : trig 15: cvt= 20, fclrt= 12 [usec], max se length=100000 b -RIO4L-3:util :-------------------------------------------------------------- -RIO4L-3:util :Name of output device = -RIO4L-3:util :Tape label = , Dismounted, file CLOSED -RIO4L-3:util : 0.000 [MB] written to tape, 0.000 to file -RIO4L-3:util :-------------------------------------------------------------- -RIO4L-3:util :Collected: 12.2552 MB, 374 Buffers, 66984 Events. -RIO4L-3:util :Rate : 98 KB/s, 3 Buffers/s, 429 Events/s -RIO4L-3:util :--------------------------------------------------------------
Shutdown data acquisition:

In order to stop to data taking, one has to issue:

mbs> stop acq
user_readout: stop acquisition triggered -rio :util :stop acquisition mbs> -rio :read_meb :found trig type 15 == stop acquisition -rio :collector:acquisition NOT running
To do a full shutdown one has to issue:
- mbs> @stop

Trouble shooting:

In case of hanging processes one can restart the system without a reboot by resetting the processes in a defined way:
- rio4l-3 nrfdaq > resl
  ---- Reset node rio rio4l-3: kill 60 # m_msg_log -rio :msg_log :exiting.. SIGTERM (kill) signal rio4l-3: Clear DAQ status... rio4l-3: Create new message files... ---- Reset node rio4l-3 finished.
If the X-terminal freezes (white stripes on the screen, no response) then you have to restart the X-windows server by:
- CTRL-ALT F1 and CTRL-ALT F7 (function keys)
Writing data files:
- The system can write data files to a RFIO server running on the host machine fwklux5 (or zirkonia) using automatic file name creation as desribed above. The file filenum.set contains the next file name to be written. To start with the first file with number nnnn you have to use:
  - mbs> connect rfio fwklux5 -disk
  - mbs> open file /data/fwkk/eposdaq/RPVS-.lmd first=nnnn size=950 -auto -rfio
  - mbs> start acquisition
This open file command takes the file specification from a file named filenum.set: This is the default procedure which avoids of having double file names, other conventions and so on. Nevertheless, you can specify the file name directly with the instructions given explicitly in man open file.

Please, try to follow the sequence of
1. mbs> open file -rfio -auto
2. mbs> start acq
3. mbs> stop acq
4. mbs> close file
all the time. This sequence avoids problems with improper file ends and arbitrarily filled single spectra.

Data analysis:
- Online data can be analysed using Go4 (GSI Object Oriented On-line Off-line system). The software should run on fwklux5. You can invoke it in the following way:
  - eposdaq@fwklux5:~> cd go4/GiPS
    eposdaq@fwklux5:~/go4/GiPS$ . go4login
    eposdaq@fwklux5:~/go4/GiPS$ go4 or
    eposdaq@fwklux5:~/go4/GiPS$ go4 GiPS-online.hotstart which will do all necessary startup commands and connect to the frontend data server.
- Because the go4 system is very powerfull and also complex, a video will be used to show you the principal steps. Don't worry if you crash the analysis, the data will be recoorded on disk and they can be analysed later again and again.
- Error handling:
- Message from MBS:
- rio4l-3 :read_meb :exiting.. SIGSEGV (segment. fault) signal
  rio4l-3 :read_meb :E-exit_daq_proc-SYSERR: System error: Out of free memory.
- Action: Close file, exit MBS and restart MBS from scratch using RESL and
- mbs> @start

Data Acquisition Manual for GiPS (Gamma-induced Positron Spectroscopy) Experiments

Starting the data acquisition from an x-terminal window:

Trouble shooting:

Writing data files:

Data analysis: