NETWORK ATTACHED DEVICES AT SNS

The Spallation Neutron Source (SNS) diagnostic instruments at Oak Ridge National Laboratory are based on the Network Attached Device (NAD) concept. Each pickup or sensor has its own resources, such as networking, timing, data acquisition, and processing. NADs function independently thus reducing the brittleness inherent in tightly coupled systems. This paper describes our implementation of the nearly 400 NADs to be deployed. The hardware consists of rackmounted PCs with standard motherboards and PCI dataacquisition boards. The software suite is based on LabVIEW and EPICS, communicating through a shared memory interface. LabVIEW supports the agile development demanded by modern diagnostic systems. EPICS is the control system standard for the entire SNS facility. Program templates and documentation tools are available to the programmer. SNS diagnostics are developed by a multi-laboratory partnership, including ORNL, BNL, LANL, and LBNL. The NAD concept proved successful during the commissioning of the SNS front-end both at LBNL and ORNL.