Loading and Checking the Hall A Trigger

Robert Michaels, rom@jlab.org, Jefferson Lab Hall A, Sept 2001

This file: hallaweb.jlab.org/equipment/daq/trigger.html

The Hall A trigger is remotely configured by CAMAC modules. The main change during an experiment is in the delays required to adjust the timings of triggers which changes with momentum and particle ID. In addition, if the power is turned off, the CAMAC modules need to be reprogrammed.

SIMPLE DOWNLOADING INSTRUCTIONS:

To download the trigger, first login to an ADAQ Linux box like adaql1 or adaql2 as ``atrig'' account. (E.g. ssh adaql1 -l atrig). The Run Coordinator should know the password. Type ``trigsetup''. An obvious graphical user interface will pop up, in which you enter the momentum and particle ID of the two spectrometers. When you are finished with a session of downloading, do not forget to press the Quit button. There is also a Help button, but you probably don't need it. The user should look for suspicious error messages in the window from which trigsetup was launched, e.g. to check if connection to the crate is ok.

EXPERT MODE:

CHECKING AND RECORD KEEPING:

FURTHER DETAILS:

One source of information on the trigger is in the Hall A Operations Manual though it tends to be out of date. hallaweb.jlab.org/document/OPMAN/index.html.

Also, here are detailed notes, which generally get updated just before we run when the final trigger configuration is settled: hallaweb.jlab.org/equipment/daq/trigsetup_coinc.html.

And here are some other relevant links about DAQ and trigger in Hall A.

The trigger manager software is based on code written by Tim Smith and Jeff Vieregg at MIT for the BLAST trigger. It is written in a framework of C++ and ROOT.

R. Michaels -- e-mail: rom@jlab.org