A CompactPCI Based Event Routing Subsystem for PET and SPECT Data Acquisition

The Quicksilver Event Routing Subsystem (ERS) is a new CompactPCI card developed as part of a new high performance data acquisition platform from Siemens Molecular Imaging (Knoxville, TN). The card´s main purpose is to route event data from the Quicksilver Event Processing Modules (EPM) out to either IEEE 1394A or PCI data collection channels. To accomplish this task, an ERS uses eight 2.0 gigabit/second serial links to the EPM backplane to receive incoming data, an outgoing 32 megabyte/second IEEE 1394A link, and an outgoing PCI interface capable of 200 megabytes/second. The card´s secondary purpose is to facilitate insertion of real-time system tagword information into the outgoing data stream such as time marks, physiological gating events, and motion axis positions. The ERS is built around a Xilinx Virtex II Pro FPGA which performs on-the-fly event packet prioritization, format translation, and flow control. This architecture allows the ERS to process up to 33 million single or coincident events per second while guaranteeing the integrity of tagword packets.