...
This section articulates the specific libraries, packages and programs that will be used to implement the LCLS high level applications.
Role of the SLC Control System.
As stated repeatedly elsewhere, the existing SLC applications, such as correlation plots, steering, bumps etc, can be used to access LCLS beamline orbit and control data. That is, SLC apps will work for LCLS. This is ensured by the "SLC-aware-IOC" project, in which VMS hosted SLC control system signals will be processed by field IOC's and data returned in a manner transparent to the VMS SLC control system.
Model based applications of the SLC control system, will require a DIMAD based model of the LCLS. Work to create that model and associated SLC DB support, has been planned and will start in the new year.
New applications however will use the architecture and tools described below.
Data Access and Control
Data access and control will be via:
- Java Channel Access (JCA). JCA is the EPICS Channel Access client used by XAL.
- Channel Access in Java (CAJ). CAJ is a Java native EPICS channel access client, which should be easier to use and higher performance, for applications that are not using XAL.
- Accelerator Independent Data Access (AIDA) gives access to SLC db, model (Twiss and R-mats), and History and EPICS archiver data, plus will soon give access to collectively controlled SLC devices (BPMs and magnets - so can acquire whole beamine at a time etc).
The choice of which of these is appropriate will vary for each application.
| Anchor | ||||
|---|---|---|---|---|
|
...