Pulsar is designed to be a general purpose test tool for the existing CDF Level 2 trigger system. It can be a data source for any data input to Level 2 decision crate, and it can be a data sink for any Level 2 data path as well. In this sense, "PULSAR" stands for "PULSer And Recorder". In the recorder mode, the data can be made available via VME access or directly into a standalone PC. The goal is to make sure CDF will have a robust Level 2 trigger with great performance well into Run2b. As of 2003, a few Pulsars prototypes have been used extensively in this mode. In particular, for testing/debugging the L1-L2 muon interface.
Since Pulsar has all the interfaces Level 2 decision crate has, in principle, it is possible to use it as a spare for the exisiting interface boards. However, since it does not have the MagicBus interface, the output will be via SVT cable which can be plugged into either a TrackList board or a MMB board to interface with the MagicBus (this will be a kludge of course). Note that this feature was not required and there was no plan to use Pulsar as spare interface board. However, in June 2003, CDF operation management requested on short notice that Pulsar be used as the muon board for the current RunIIa L2 system. As a result, after summer of 2003, one Pulsar prototype board has been used as muon interface board and has been running in the current existing RunIIa L2 system with beam, and becomes the official L2 muon board for RunIIa.
Since Pulsar is designed to have all the interfaces Level 2 decision crate has, and it also has SLINK interface, it can be used to upgrade our Level 2 decision crate for Run2b. Pulsar can convert the input data for Level 2 trigger into S-LINK format for each data path and send it out via P3 connector into a S-LINK interface LSC card (Link Source Card) which is mounted on a simple VME64x transition module similar to S2VME64x. Since each Pulsar also has the Level 1 trigger and Track trigger information available, it can use that information to suppress or re-organize the input data, this could be useful (for example) to suppress large Muon data input. The raw input data is available via VME readout upon Level 2 Accept. In this sense, Pulsar is a Pre-processor interface board with readout capability. The output data can be sent to a LDC card (Link Destination Card), which in turn can be plugged into another Pulsar board via the front mezzanine card connector. Up to 4 LDCs can be plugged into one Pulsar board, and the fragment S-LINK data packages from different subsystems can be then merged into one data package at event level, and again can be sent out in S-LINK format via P3. In this sense, Pulsar is a S-LINK merger. The final S-LINK data package can then be sent into a PC via S-LINK to PCI card. The PC running Level 2 decision algorithm can then send the decision information (with a few S-LINK words) back into Pulsar via PCI to S-LINK card. Pulsar can then pass (and handshake) the decision to Trigger Supervisor through the TS interface.
As of June 2004, 12 Pulsars are running in the system as SVT Road Warrior. To learn what Road Warrior does, see Franco's early report on Pulsar_SVT_RW (ppt) .
Pulsar can be used for SVT II upgrade. Now it is an offical project, see RunIIb SVT upgrade web page . For early discussions, see talks related to using Pulsar in SVT: Introduction to Pulsar (Ted) and Using Pulsar for SVT upgrade (Alex) ; SVT workshop summary (ppt) or SVT workshop summary (ps) .
Pulsar will be used for XFT upgrade. Now it is an offical project, see RunIIb XFT upgrade web page . In this case, Pulsar is used to transfer XFT stereo information from the new XFT into Level 2. XFT opitcal mezzanien cards will be designed to be compatible with Pulsar.
With a GLINK mezzanine card, Pulsar can also source data for (fiber data to Hit-Finder) the Silicon Vertex Trigger (SVT) system. In fact, when Pulsar is in SRC mode (see below), it is already a pulser for SVT Hit Finder because Pulsar-SRC has the the Glink Tx.
Pulsar is designed to be compatible with SRC and can be used for SRC upgrade. We are now discussing this possibility (as of Dec. 2003). Details can be found at the talk Initial thoughts on Pulsar in SRC mode, ppt format . Other SRC related documentation can be found here: SRC (ps) , SRC (pdf) , src_changes (ps) , src_changes (pdf) , srctm (ps) and srctm (pdf) .
With the mezzanine card approach, it is posible to use Pulsar to sink (or spy) other types of data (Hotlink/Taxi/GLINK/LVDS/...etc) and make them available for online monitoring for CDF DAQ/trigger system.
With the mezzanine card connections, VME interface as well as the capability to communicate with a PC via high bandwidth S-LINK cards, it is possible to use Pulsar as a simple DAQ system such as in a test beam environment. It may be even possible to use it as a general purpose diagnostic tool for Beams Division to improve the diagnostic capability for the Tevatron Collider Complex...