BNMR Experiments at TRIUMF
These pages describe the Data Acquisition System for the BNMR and BNQR experiments at TRIUMF
There are two experiments defined for BetaNMR :
- BNMR running ON the BNMR high-voltage platform
- BNQR running on the BNQR high-voltage platform
Each has their own VME Crate containing a VMIC cpu and modules (see Hardware), and each runs as a separate MIDAS experiment. The DAQ software is mostly common to both experiments, differences being handled by "ifdefs".
There are two Beamline modes that BNMR and BNQR experiments can be run in:
- single channel mode where the beam is sent to one channel only, either BNMR or BNQR
- dual channel mode, where the beam is switched between the two channels BNMR and BNQR.
where the main EPICS system is used to control the beam.
For both BNMR and BNQR experiments, two types of environment are defined (cf MUSR experiments):
- Integral (Type 1)
- Time Differential or TD (Type 2)
- Combination of the above two types
A number of different Experimental modes are defined for each of Type 1 (Integral) and Type 2 (TD). These allow different experimental modes to be run (e.g. Frequency scan, Na Cell scan).
DAQ hardware components for each system (BNMR/BNQR) include the following VME modules:
|Module||Description||Manual||VME Base Address||BNMR||BNQR|
|SIS3801 version E||multichannel scaler A||SIS3801||0x2800||yes||yes|
|SIS3801 version E||multichannel scaler B||0x1800||yes||no|
|PPG (Pulseblaster)||Pulse Programmable module||PPG
|PSM||Pol Synthesizer module (RF)||PSM / PSMII
|PSMII||Pol Synthesizer module II (RF)||0xC00000||yes||no|
|MVME162||68040 board, cpu runs CAMP (VxWorks)||yes||yes|
|VMIC||cpu runs frontend (Linux)||yes||yes|
CAMP host: MVME162 68040 board, front end computer for CAMP .
The DAQ system is based on the MIDAS package. The experiment is controlled using the MIDAS webserver (mhttpd). Due to the large number of experimental parameters required, Midas custom pages have been written for BNMR/BNQR experimenters to control and monitor their experiment. A custom logger (mdarc/midbnmr) saves the data into MUSR MUD format files, and the MUSR CAMP slow control system is used for slow controls. Analysis is done by physica.
The main software components of the BNMR/BNQR experiment are
|frontend (runs on VMIC)||set up, operate and read hardware modules|
|rf_config||check PPG parameters, download program to PPG|
|mdarc||custom data logger saves data in MUD format|
|midbnmr||converts MIDAS format saved data files to save in MUD format|
|mheader||sends out CAMP and EPICS slow-control data to be saved in the MUD data file|
|fe_epics||sends experimental data to EPICS (can be read by control-room)|
|perlscripts||various perlscripts control changing experimental mode, checking and maintaining run numbering, etc.|
|autorun||automatic run controller|
|lcrplot||plots experimental data|
|physica||analyse data, reads MUD format files|
The DAQ software components are started by the script start-all and stopped by the script kill-all.
- The VMIC front end computer runs the frontend code which
- controls PSM,PPG, VMEIO
- acquires data from SIS MCS module(s), builds histograms
- acquires data from CAMP, EPICS
- sends the data out into the data buffer
- The host computer (isdaq01)
- run all other software components
- starts/stops runs
- acquires the data from the data buffer
- logs the data
- monitors the experiment