50 likes | 168 Views
TKR Trigger Timing. We need guidance to understand results from data analysis with cosmic rays when TEM diagnostics are enabled As Mike points out this is NOT the default mode on orbit when the LAT is fully assembled our tests should not be dependent on the TEM diagnostics
E N D
TKR Trigger Timing • We need guidance to understand results from data analysis with cosmic rays when TEM diagnostics are enabled • As Mike points out this is NOT the default mode on orbit • when the LAT is fully assembled our tests should not be dependent on the TEM diagnostics • Currently diagnostics are being used to • Understand if trigger primitive and strip data are consistent under several instrument configurations • What does consistent mean? (see next slide) • Evaluate trigger efficiencies (TKR)
Cosmic Ray data: 1 and 2 tower tests • Question: • If a trigger primitive(Treq) fired in one plane, shall we have a strip hit (digi) in that plane? 5 tick window “missing” strip hits “missing” trigger primitives 12 tick window
TKR Trigger Timing for cosmic rays • We decided to revisit the “timing” diagram (thanks for the input Mike) because of differences in the instrument configuration between 1 and 2 tower tests • Trigger window width • Single tower • 5 ticks (250ns) • We sample diagnostics near the opening of the window (see last 2 slides) • Two tower • 12 ticks (600ns) • We sample diagnostics near the closing of the window (see last 2 slides • TKR hold delay for TEM diagnostics (same for all tests) • 9 ticks (450ns)
TKR Diagram: Single Tower Tests 150 ns 100 ns 150 ns 250 ns 100 ns GEM FE RC TEM TEM RC FE N = 5 1 + (5) 1 1 2 1 2 + (0) 1 1 Trigger Engine checks to see if there is no inhibit nor prescale and issue a Trigger Acknowledge Message (TAM) Receive TAM Process TAM Form (TACK) signal send it out Width of coincidence window First trigger type to arrive opens the window All trigger types will set a bit in the Gem Condition Summary Word (correct in SVAC ntuple Wrong in merit ntuple) W If analog fast OR is 1 issue a TREQ Send TAM from GEM to TEM X Latch Trigger primitives Latch Data TREQ are stored in a buffer. Only AFTER we know that a valid trigger happened (TAM + TACK) the trigger primitives can be latched. In this separate line a delay of at least 7 ticks = 350 ns (X) should be added to hold the TEM diagnostic information. We set to 9 ticks=450 ns Collect charge and transfer to the end of the plane GTIC makes a 3-in-a-row out of TREQs and (align) them GTIC knows about masks (layers,cables…) 750 ns
TKR Diagram: Two Tower Tests 600 ns 150 ns 100 ns 150 ns 100 ns GEM FE RC TEM TEM RC FE N = 12 1 + (3) or (4) 1 1 2 1 2 + (0) 1 1 Trigger Engine checks to see if there is no inhibit nor prescale and issue a Trigger Acknowledge Message (TAM) Receive TAM Process TAM Form (TACK) signal send it out Width of coincidence window First trigger type to arrive opens the window All trigger types will set a bit in the Gem Condition Summary Word (correct in SVAC ntuple Wrong in merit ntuple) W Latch Trigger primitives X If analog fast OR is 1 issue a TREQ Send TAM from GEM to TEM Latch Data TREQ are stored in a buffer. Only AFTER we know that a valid trigger happened (TAM + TACK) the trigger primitives can be latched. In this separate line a delay of at least 7 ticks = 350 ns (X) should be added to hold the TEM diagnostic information. We set to 9 ticks=450 ns Collect charge and transfer to the end of the plane GTIC makes a 3-in-a-row out of TREQs and (align) them GTIC knows about masks (layers,cables…) 1100 ns