National Synchrotron Light Source Symposium

The GM/CA CAT has been established by the National Institutes of Health's National Institute of General Medical Sciences and National Cancer Institute to build and operate a national user facility for protein crystallography at the Advanced Photon Source. The facility provides two insertion device beamlines based on a canted undulator design and a bending magnet line. With the two ID lines fully operational and the BM line already installed, most of the pieces of the
control system have been put in place, tested by users and refined. This presentation gives anoverview of what has been implemented and outlines further plans.

The GM/CA CAT deploys EPICS for the low-level controls including two VME IOCs per beamline, an embedded IOC for bimorph focusing mirrors and several Linux-based EPICS IOCs interfacing MAR CCD, beamline equipment protection system, and etc. An essential highlight of the system is the deployment of the Delta Tau Turbo PMAC Ultralite motion controllers that we made available in EPICS. The extended functionality of PMACs is used to implement
coordinated motions at the beamline and synchronize motions with digital I/O: for example, goniometry with a fast X-ray shutter.
On top of EPICS, we have built a collection of beamline optimization tools based on on-the-fly scanning algorithms and data acquisition software for which we implemented an EPICS port of BLU-ICE by SSRL. The latter was reduced to a regular EPICS client similar to MEDM being assisted by multiple state-notation-type EPICS servers, such as a frame processing engine, fluorescence scan engine, sample centering server, frame audit server, and etc. For automatic
sample centering we have interfaced the packages C3D by Lavault Bernard at ESRF and XREC by Viktor Lamzin’s group at DESY. For automated sample mounting, we have installed the ALS-style robots and developed EPICS controls for them.

The computing infrastructure has been designed as a combination of Linux and Windows works