TRT ROD

• ROD position in TRT readout

• ROD functionality, block scheme
• Data flow
• Event building and header
• Zero suppression
• Test and calibration tools
• VME, monitoring

• data volume

• latency and dead time

• miniROD

• ROD crate

• error detection

• monitoring

• calibration and initialisation

• numbers

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ROD functionality, block scheme

Data flow

 

Event building and header

 
 
 

Zero suppression

 
 
 

Test and calibration tools

 
 
 

VME, monitoring

Data volume

• Input data bandwidth: 4.16 Gbits/s

• Output data bandwidth < 800 Mbits/s

• depends on luminosity (see graph)

• does not depend on trigger type (data format)

• depends on trigger type (physics)

• TRT ROD does not introduce dead time
• frontend electronics
• S-LINK

• latency
• frontend to ROD
• ~10 us single event
• ~ n*10 us bunch of n consecutive events
• ROD input to output
• ~ 40 clock cycles depending on event contents and zero suppression
• OR latency of trigger type info if longer

• mini-ROD (1/4 of a ROD; no S-Link and ZS) done
• DSP evaluated
• FPGA chosen

• Half-ROD with S-Link in 99

• Full ROD in 2000

• 1 TRT_TTC for 3 RODs

• 1 BUSY module, 12 RODs, 4 TTCs, CPU

• Standard
• VME 9U
• P3 with custom backplane and coax/optical connection (ERNI)
• +5V,+3.3V power supply

• Synchronisation
• BCID mismatch
• L1ID mismatch

• Frontend status
• PLL locked
• ROC startup

• on board buffers
• Empty, Almost Empty, Almost Full, Full flags
• advanced BUSY signal (programmable)

• Crate level
• monitoring
• sampling data
• hitmaps

• higher levels?

• Mandatory at the ROD level
• Zero-suppression is destructive
• Not foreseen to transmit the full data to the ROBs
• On a fraction of the events
• hitmaps

• Error check and logging
• All level (previous slides)

• Monitoring linked to level-2
• At the ROB level

• Local crate
• both non/zero suppressed data available from ROD with programmable sampling rate
• sampling will be adjusted to the VME bandwidth and processing power of CPU. Typically ~1% of all events
• example: readout of 1% of the events with 75kHz trigger rate in VME crate requires 80 MB/s bandwidth

• Stand-alone runs
• Phase adjustment for the front-end read-out (before each run) - ROD level
• Test-pulse / trigger - ROD and ROB level
• Thresholds scan - ROD and ROB level

• Timing set-up
• Timing adjustment in ROD crate
• necessity to have the tools
• Without beam. CTP special mode Prepulse/ L1A - ROD or ROB level
• With beam. "Random" L1A - ROD or ROB level

• During physics
• Not foreseen but not yet ruled out
• Would be during the gap

• Access to database
• No specific requirements on the organisation
• 425000 channels
• Several 1-bit fields (e.g. mask)
• Some parameters shared by 8 or 16 channels (e.g. thresholds)

• Detector
• End-cap
• 18 wheels per side
• 150000 channels per side
• Barrel
• 96 modules of 3 different types per side
• 50000 channels per side
• 27000 links (40Mbits/s)

• Electronics
• 104 frontend links/ROD (1664 channels)
• 256 RODs for the whole TRT
• 22 VME 9U crates

• Program
• miniROD now
• half ROD 1999
• full ROD 2000