DAQ system: Difference between revisions
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poly 906 347 906 367 977 395 1022 369 1025 345 977 367 [[Collector Box]] | poly 906 347 906 367 977 395 1022 369 1025 345 977 367 [[Collector Box]] | ||
poly 1034 287 1103 301 1146 275 1146 299 1100 323 1042 311 [[Collector Box]] | poly 1034 287 1103 301 1146 275 1146 299 1100 323 1042 311 [[Collector Box]] | ||
poly 199 104 137 158 206 175 269 139 [[DAQ Power Supply]] | |||
poly 312 42 253 96 317 113 375 58 [[DAQ Power Supply]] | |||
poly 902 339 966 285 1034 321 976 356 [[DAQ Power Supply]] | |||
poly 1021 278 1081 224 1280 846 1091 294 [[DAQ Power Supply]] | |||
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Gammasphere's DAQ system (data acquisition system) is now placed on relay racks by each of its four "hemispheres". Each of the racks for the DAQ consists of a [[DAQ Power Supply|power supply]], a [[Collector Box|collector box]], and a [[VME Crates|VME crate]]. The data acquisition system observes, interprets, and modifies data taken from [[Gammasphere]] and appropriately presents it to the user. | Gammasphere's DAQ system (data acquisition system) is now placed on relay racks by each of its four "hemispheres". Each of the racks for the DAQ consists of a [[DAQ Power Supply|power supply]], a [[Collector Box|collector box]], and a [[VME Crates|VME crate]]. The data acquisition system observes, interprets, and modifies data taken from [[Gammasphere]] and appropriately presents it to the user. | ||
Revision as of 22:13, February 23, 2023
Gammasphere's DAQ system (data acquisition system) is now placed on relay racks by each of its four "hemispheres". Each of the racks for the DAQ consists of a power supply, a collector box, and a VME crate. The data acquisition system observes, interprets, and modifies data taken from Gammasphere and appropriately presents it to the user.
When Gammasphere collects data, single-ended signals are first collected from the slope box for the Ge Center, Ge Sides, and BGO segment. The signals are converted to differential signals by the SBX, and are then sent to the collector box so the signals can properly be routed to the digitizers. The digitizers process and output the desired information to the user based upon their data specifications. The DAQ system is an FPGA-based design that provides communication hub interfacing the preamp, power board, dongle and slope box to EPICS through serial interface. Analog signal paths are completely software controlled.
DAQ System Function
The DAQ system prior to upgrades consisted of VME crates, IOC Modules, Digitizers and Trigger Modules. There were two types of Digitizers (Master and Slave) and well as Trigger (Master and Router). In the current version of the upgraded Gammasphere DAQ system, some of the old hardware is still used, but in a different way. All channels in all digitizers run continuously. When discriminator logic marks leading edges of gamma-ray signals, energy sums, timing and other data are stored in a header identifying the event. If the event is selected for readout by the trigger system, the header and a programmable amount of waveform is transferred from the channel to the board-wide FIFO (first in, first out) data holder. The IOC scans the FIFOs to see if there is data to read out. If so, the IOC reads it out into buffers. A program called “gtReceiver” sends messages to each IOC when the receiver is ready for more data. The IOC then breaks apart buffers into UDP packets and sends them to gtReceiver. The gtReceiver program then routes the packets to files that may be organized by digitizer or by channel.
DGS Commander EPICS Screens
This section contains an image map of DGS Commander and all subsequent EPICS screens.
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