SNS Diagnostics Timing Integration

The Spallation Neutron Source (SNS) accelerator systems will deliver a 1 GeV, 1.44 MW proton beam to a liquid mercury target for neutron scattering research. The accelerator complex consists of a 1 GeV linear accelerator, an accumulator ring and associated transport lines. The SNS diagnostics platform is mostly PC-based running Windows XP Embedded for its OS and LabVIEW as its programming language. Coordinating timing among the various diagnostics instruments with the generation of the beam pulse is a challenging task that we have chosen to divide into three phases. First, timing was derived from VME based systems. The second phase, described in this paper, timing pulses were generated by an in house designed, PCI timing card installed in ten diagnostics PCs. Because each timing card has up to four available triggers and we could duplicate triggers using a distribution fan out module, enough triggers were generated for all instruments. This paper describes how the Timing NAD (Network Attached Device) was rapidly developed using our NAD template, LabVIEW’s PCI driver wizard, and LabVIEW Channel Access test screens. The NAD was successfully commissioned and has reliably provided triggers to the instruments. This work supports the coming third phase where every NAD will have its own timing card.