How it Works
This section describes:
- The software components that cooperate to integrate controls
data with the experiemnal event file.
- An overview of the step by step procedure to
include controls information in experiment event files.
The figure below shows schematically how the system works:
Component Block Diagram
The key components are:
- Production Readout A new production quality readout program.
this program has many additional features however the two which are
important to this document are:
- The program can function as a TCL server, allowing it to accept
TCL commands from external programs (similar to the scaler
display program).
- TCL Scripts can designate TCL variables in as run variables. Run Variables are periodically logged to the
event file.
- Epics Archiver A tcl server client that takes a list of control
system channel names and maintains in its server (Production Readout)
a pair of arrays:
- EPICS_DATA(channel_name) contains the value
of a channel named channel_name.
- EPICS_UNIT(channel_name) contains the units
of a channel named channel_name.
To use these components to integrate controls and event data you must:
- [ ]Port any existing readout software to the production
readout software framework.
- [ ]Configure the EPICS archiver so that it will connect
to the Readout program and maintain the desired set of
channel information in the EPICS_DATA and EPICS_UNIT arrays.
- [ ]Write a script that allows the epics archiver to connect
to the readout program.
- [ ]Write a script that designates elements of the
EPICS_DATA and EPICS_UNIT arrays as run variables.
- [ ]Write a script to start up the readout program with the
desired command line switches.
Report documentation errors to
Ron Fox
(fox@nscl.msu.edu)or
NSCL's Bugzilla page
