Level 1 Calorimeter Trigger Resources programmed by COOR -------------------------------------------------------- Philippe Laurens, MSU -- 1-Apr-2002 I. Introduction =============== 1. General ---------- The Level 1 Calorimeter Trigger processes the 1280 Electro-Magnetic (EM) and 1280 Hadronic (HD) Trigger Tower energy analog input signals coming from the Calorimeter Base Line Subtractor (BLS) Cards.. Using this information the Level 1 Calorimeter Trigger computes the Transverse Energy deposited in each Trigger Tower and calculates scalar energy sums over the whole detector. A vector sum is also computed to give a missing momentum. Each resulting Global Sum can be programmed to a number of global thresholds. cf. I.4 and II.3. The Level 1 Calorimeter Trigger also produces several counts of Trigger Towers above some programmable thresholds. Each resulting Global Count can be programmed to a number of global thresholds. cf. I.2, II.1, and II.2. In addition to counts of Trigger Towers the Level 1 Calorimeter Trigger also produces counts of larger objects called Large Tiles (made of fixed non-overlapping groups of Trigger Towers) above some programmable thresholds. cf. II.1.d, and II.2.c. The above programmable resources were already available during Run I. Additional intermediate information will be made available for Run II to help in matching the trigger decision from the Calorimeter Trigger to the information from other detectors. New triggering resources will also be available for Run II. Two additional Trigger Tower Reference Sets (one EM, one TOT=EM+HD) will be available to generate the Trigger Tower Seed Masks sent to and used by the Level 2 Calorimeter Trigger Pre-Processor. These are called the Seed Reference Sets. COOR programs the Level 1 Calorimeter Trigger by sending command messages to the Trigger Control Computer (TCC) which accepts ITC client connections on TCP port #52160. COOR commands are ASCII messages made of a command ID and a message payload. Other COOR documents (*) describe this protocol in detail. This file describes the content of the messages and how COOR can control the Level 1 Calorimeter Trigger resources. (*) http://www-d0.fnal.gov/d0dist/dist/packages/coor/devel/doc/coorover.ps 2. Reference Sets ----------------- a) Definition ------------- The Level 1 Calorimeter Trigger builds several counts of Trigger Towers carried over the whole detector. There are two different types of global counts and four separate sums are built for each type of count. The first type of count collects the Electro-Magnetic (EM) Trigger Towers. A Trigger Tower will be included in an EM Trigger Tower Count only if its EM energy deposit reached or exceeded its programmed transverse energy minimum threshold. Optional vetoes can also be programmed for the Hadronic (HD) Trigger Towers. A Trigger Tower will be included in an EM Trigger Tower Count only if its Hadronic energy deposit did not reach or exceed its programmed HD transverse energy veto. The Second type of count concerns the Total (TOT, i.e. Electro-Magnetic + Hadronic) Trigger Towers. A Trigger Tower will be included in a TOT Trigger Tower Count only if its Total (=EM+HD) energy deposit reached or exceeded its programmed transverse energy minimum threshold. b) Vocabulary ------------- Since these thresholds can be separately programmed for each trigger tower, the name "Reference Set" was chosen to characterize the set of all individual thresholds of a given type specified over all 1280 Trigger Towers (40 eta * 32 phi). There are thus three types of Trigger Tower Reference Sets called the Electro-Magnetic Transverse Energy (EM Et) Reference Set, the Hadronic Veto (HD Veto) Reference Set, and the Total Transverse Energy (TOT Et) Reference Set. Four separate Reference Sets are available for each type, numbered from 0 to 3. The EM Et Reference Set #0 (respectively 1, 2 or 3) is associated with the HD Veto Reference Set #0 (respectively 1, 2 or 3) to produce the EM Trigger Tower Count #0 (respectively 1, 2 or 3). A similar type of reference set is used for the Large Tiles as described in II.1.d. c) Typical Reference Set Programming and Syntax Guidelines ---------------------------------------------------------- The values of the thresholds in each reference set are most likely to be chosen uniformly constant over the whole detector, or show a small number of discontinuities in eta phi between which the threshold remains uniformly constant. It is even more likely for the thresholds to be chosen uniformly constant for all the 32 phi values of Trigger Towers at a given eta. It is also most likely for the thresholds to be chosen symmetric with respect to the z=0 plane, that is have identical thresholds for eta and minus eta. A special effort is made in the choice of syntax below in order to (a) be intuitive (b) summarize the information transferred (c) enhance the singularities (d) emphasize the pattern of the thresholds over the detector, (e) and its eventual symmetries. The syntax for addressing Trigger Towers should also (a) allow for easy programming of groups of towers specified as ranges in eta and phi indices, (b) without losing the ability to address an individual tower, (d) allow to program typical cases in a single message, (e) but also allow a multi-part definition for complicated patterns, (f) allow omissions e.g. of the phi range for an azimuthally uniform range. d) Generic Syntax Definition ---------------------------- Examples: L1CT_Ref_Set TT_Eta(-20:20) TT_Phi(1:32) Value 10.0 The first keyword, "L1CT_Ref_Set", introduces all Reference Set definitions. The second keyword, "", specifies the type of Reference Set as described in I.2.a (EM Et, HD Veto, or TOT Et). The "" keywords are defined below in II.1.a,b,c. The "" is the ID number of the Reference Set, between 0 and 3. A set of magnitudes of eta is specified by the keyword "TT_Eta" followed by a pair of parenthesis delimiting any combination of individual eta Trigger Tower indices and/or ranges of eta indices. TT_Eta values are the Trigger Tower pseudo-rapidity indices. TT_Eta values are signed integers between -20 and -1 and +1 and +20. The plus sign ("+") is NOT necessary but accepted. A range is specified by its upper and lower bounds separated by a colon character (":"). The lower (respectively upper) bound is the number appearing before (respectively after) the colon character. Extra space characters may appear before and after the colon character. When two eta magnitudes are separated by a colon to form a range, they are understood as representing the complete set of all integer values between and including the upper and lower bounds. There is no requirement in the order of upper and lower range bounds with respect to their sign or magnitude: (-2:+2), (+2:-2), (2:2) are legal range definitions. When an eta index is not separated by a colon character from either of its surrounding index values it will be understood as one more discrete values to be included in the set of magnitudes defined inside the parenthesis. Multiple ranges and/or multiple discrete values may be specified within the same set of parenthesis, each separated by at least one space character. The specification of the eta indices may be omitted when all existing magnitudes are to be treated identically; it is equivalent to TT_Eta(-20:20). A pair of empty parenthesis following "TT_Eta" is equivalent to omitting the eta indices. The keyword "TT_Eta" must always be followed (after optional space characters) by a set of parenthesis including the Eta indices. A set of phi values is specified by the keyword "TT_Phi" followed by a pair of parenthesis including any combination of individual phi values and phi ranges. TT_Phi values are the Trigger Tower azimuthal indices. TT_Phi values are unsigned integers between 1 and 32. A plus sign ("+") is NOT necessary but accepted. The syntax rules for specifying TT_Phi values are identical to the syntax rules for the TT_Eta defined above. The specification of the phi values may be omitted when all existing phi values are to be treated identically; it is equivalent to TT_Phi(1:32). A pair of empty parenthesis following "TT_Phi" is equivalent to omitting the Phi indices. The keyword "TT_Phi" must always be followed (after optional space characters) by a set of parenthesis including the Phi indices. When both the Eta and Phi indices are omitted the Reference Set is programmed uniformly over all Trigger Tower. The Keyword "Value" must appear after the Trigger Tower specification. The Keyword "Value" is followed by the Energy Threshold Value specified as a floating point number in units of GeV of z-corrected Transverse Energies. The decimal point is not required in the specification of the Threshold Value. For thresholds below 1 GeV, a leading 0 must be explicitly specified before the decimal point. The Trigger Control Computer will perform the translation to the nearest quantified threshold value that will be inclusive of the requested value, as defined earlier. Only one Threshold value may be defined within a single message. Whenever a range of Trigger Tower appears in a message, the following threshold value is applied to the specified Reference Set and to all the Trigger Towers specified in the range. Trigger Towers outside of the specified range are not affected. When successive Trigger Tower ranges overlap for the same reference set the threshold value programmed for the overlapping tower(s) is the one specified for the last occurrence. This may be useful to first define a uniform reference set and subsequently modify it by adding singularities. The Keywords must be specified in the order described except for the "TT_Eta" and "TT_Phi keywords which may be reversed. These two keywords may also appear zero or multiple times. Setting the Reference Set thresholds is independent from the programming of the global thresholds acting on the total count carried over the whole detector for the number of towers exceeding their individual threshold. The global thresholds are programmed with separate messages. cf. I.4. h) examples of range specification ---------------------------------- L1CT_Ref_Set TT_Eta(-20:20) TT_Phi(1:32) Value 10.0 L1CT_Ref_Set TT_Eta(-20:20) Value 10.0 L1CT_Ref_Set Value 10.0 Either of these three messages specifies a uniform threshold of 10.0 GeV over all Trigger Tower eta indices within [-20,-1] and [1,20] and phi indices within [1,32] L1CT_Ref_Set TT_Eta(-20 20) Value 1000 L1CT_Ref_Set TT_Eta(-19:-13 13:19) Value 20 L1CT_Ref_Set TT_Eta(-12:12) Value 10 These three messages taken together specify a Reference Set of 10.0 GeV over all Trigger Tower eta indices within [-11,-1] and [1,11], 20.0 GeV over all Trigger Tower eta indices within [-19,-13] and [13,19], and excluding all Trigger Towers with eta index -20 or 20. This Reference Set is uniform with respect to the phi index for all values [1,32]. L1CT_Ref_Set TT_Eta(-2) TT_Phi(15) Value 1000.0 This message specifies or modifies the Threshold value for the Trigger Tower with eta index -2 and phi index 15 to effectively exclude this Trigger Tower from contributing to the Reference Set. 4. Global Thresholds -------------------- L1CT_Count_Threshold Ref_Set Comparator 1 Value 1 L1CT_Energy_Threshold Comparator 0 Value 55.5 Each EM Et (with associated HD Veto) or Tot Et Reference Set produces a Global Count of Trigger Towers carried over the whole detector. A Global Threshold can be applied to this Global Count, and the binary result of this comparison is sent to the Level 1 Trigger Framework as an And-Or Term Input. Several Global Thresholds can be applied to the same Global Count, each resulting in a separate And-Or Term. The Calorimeter also builds a number of Global Energy Sums carried over the whole Detector (Global TOT Et, Global Missing Pt, etc) as described later in this document. Each Global Energy Quantity can also be compared to a number of Global Energy Thresholds, each resulting in a separate And-Or Term sent to the Level 1 Trigger Framework. The number of Global Thresholds available for each Global Count or Global Energy may change over the life of the experiment and COOR will read from its configuration files how many Thresholds are available for each resource. COOR will also read from its configuration files how the outputs from all the comparisons map onto the 256 L1 Framework And-Or Input Terms. The programming of a Level 1 Calorimeter Trigger Global Threshold Value is independent from the programming of the Level 1 Framework And-Or Network for each Specific Trigger to include or ignore each particular And-Or Term. The first keyword is "L1CT_Count_Threshold" for Trigger Tower Count Thresholds and "L1CT_Energy_Threshold" for Energy Thresholds. The second keyword is "" or "" and specifies the type of Count or Energy Resource being programmed. For Count Thresholds the keyword "Ref_Set" follows with an associated "" value between 0 and 3. The keyword "Comparator" is followed by the number of the comparator being programmed. The comparator number lower value is 0, while the upper value depends on the particular resource and is not determined at this time. The Keyword "Value" is followed by the Global Threshold Value. Trigger Tower Count Thresholds only accept positive integer numbers. Energy Thresholds accept floating point values with optional decimal point. The Keywords must be specified in the order described here. Several "Comparator" and "Value" keywords may be specified in the same message with their associated values. These commands do NOT accept negative numbers. All unspecified Global Comparator Thresholds are not modified. All values are interpreted as inclusive. This means that the And-Or term resulting from the comparison of a Global Count or Energy against the specified threshold will be asserted as soon as the Count or Energy Value is equal to or greater than the specified Global Threshold. II. L1CT Resources Classic from Run I ===================================== 1. Reference Set ---------------- a) EM Et Reference Set ---------------------- L1CT_Ref_Set EM_Et_Ref_Set 0 TT_Eta(-20:20) TT_Phi(1:32) Value 10.0 L1CT_Ref_Set EM_Et_Ref_Set 0 Deallocate Generic description of the syntax for this command is described in I.2.f. The Keyword "EM_Et_Ref_Set" is used to identify an EM Et Reference Set. There are 4 EM Et Reference Sets, numbered 0 thru 3. Each EM Et Reference Set is associated with the HD Veto Reference Set with the same ID number. A Trigger Tower will be included in an EM Trigger Tower Count only if its EM energy deposit reached or exceeded its Reference Threshold. An Optional veto can be programmed for the corresponding Hadronic (HD) Trigger Tower. A Trigger Tower will be included in an EM Trigger Tower Count only if its Hadronic energy deposit did not reach or exceed its programmed HD Veto Threshold. EM Et Reference Set Thresholds will be quanticized by TCC in steps of 1/4 GeV. e.g. a value of 10.8 GeV will be translated into the nearest inclusive value of 10.75 GeV. The default value of the programming of all EM Et Reference Set Threshold Comparators is defined at full scale, thus guaranteeing that Trigger Towers not explicitly programmed cannot participate in the Global Count of Towers above the EM Reference Set. The Keyword "Deallocate" causes TCC to return the specified Reference Set to its default value. Note: Deallocating an EM Et Reference Set also implicitly deallocates its matching HD Veto Reference Set. b) Hadronic Veto Reference Set ------------------------------ L1CT_Ref_Set HD_Veto_Ref_Set 0 TT_Eta(-20:20) TT_Phi(1:32) Value 10.0 L1CT_Ref_Set HD_Veto_Ref_Set 0 Deallocate Generic description of the syntax for this command is described in I.2.f. The Keyword "HD_Veto_Ref_Set" is used to identify an Hadronic Veto Reference Set. There are 4 HD Veto Reference Sets, numbered 0 thru 3. Each HD Veto Reference Set is associated with the EM Et Reference Set with the same number. A Trigger Tower will be included in an EM Trigger Tower Count only if its EM energy deposit reached or exceeded its Reference Threshold. An Optional veto can be programmed for the corresponding Hadronic (HD) Trigger Tower. A Trigger Tower will be included in an EM Trigger Tower Count only if its Hadronic energy deposit did not reach or exceed its programmed HD Veto Threshold. HD Et Reference Set Thresholds will be quanticized by TCC in steps of 1/4 GeV. e.g. a value of 10.8 GeV will be translated into the nearest inclusive value of 10.75 GeV. The default value of the programming of all HD Veto Reference Set Threshold Comparators is defined at full scale, thus guaranteeing that Trigger Towers not explicitly programmed with an Hadronic Veto simply do not use and are not affected by the HD Veto feature. The Keyword "Deallocate" causes TCC to return the specified Reference Set to its default value. c) Tot Et Reference Set ----------------------- L1CT_Ref_Set TOT_Et_Ref_Set 0 TT_Eta(-20:20) Value 10.0 L1CT_Ref_Set TOT_Et_Ref_Set 0 Deallocate Generic description of the syntax for this command is described in I.2.f. The Keyword "TOT_Et_Ref_Set" is used to identify an TOT Et Reference Set. There are 4 TOT Et Reference Sets, numbered 0 thru 3. A Trigger Tower will be included in a TOT Trigger Tower Count only if its TOT energy deposit reached or exceeded its Reference Threshold. TOT Et Reference Set Thresholds will be quanticized by TCC in steps of 1/2 GeV. e.g. a value of 10.6 GeV will be translated into the nearest inclusive value of 11.0 GeV. The default value of the programming of all TOT Et Reference Set Threshold Comparators is defined at full scale, thus guaranteeing that Trigger Towers not explicitly programmed cannot participate in the Global Count of Towers above the TOT Et Reference Set. The Keyword "Deallocate" causes TCC to return the specified Reference Set to its default value. d) Large Tile Reference Set --------------------------- L1CT_Ref_Set Large_Tile_Ref_Set 0 TT_Eta(-20:-13) Value 1000.0 L1CT_Ref_Set Large_Tile_Ref_Set 0 Deallocate In addition to the Trigger Tower 4 EM and 4 Tot Et Threshold Reference, the Level 1 Calorimeter Trigger also makes Large Tile (4 x 8 Trigger Tower in eta x phi) Tot Et Energy signals and offers 8 Large Tile Threshold Reference Sets to produce 8 Large Tile Counts. Large Tile Reference Sets are independent and separate from the Trigger Tower based Reference Sets described in II.1.a,b,c above. The Large Tile segmentation in TT_Eta magnitude is 1-4, 5-8, 9-12, 13-16, 17-20, and in TT_Phi is 1-8, 9-16, 17-24, 25-32. The Large Tile Reference Sets are specified with the same syntax as the Trigger Tower Reference Sets. No new Trigger Tower indexing scheme is introduced for the Large Tiles. There is however one additional syntax constraint for the Large Tile Reference Sets which do not apply to the Trigger Tower Reference Sets. The constraint is that any boundary used to define a range of Trigger Tower Indices cannot cut across the coverage of a Large Tile, that is any range specified must cover an integral number of Large Tiles. e.g. TT_Eta(12:20) is an illegal range as it totally includes the Large Tiles covering TT_Eta indices 17-20, and 13-16 but cuts across the Large Tile covering TT_Eta indices 9-12. If an invalid range is specified TCC will return a "Bad" acknowledgement message and take no action. Each of the 8 Large Tile Counts built from the 8 Large Tile Reference Sets is compared to 3 fixed Large Tile Count Thresholds, namely ">=1", ">=2", and ">=3". There are thus no Large Tile Count Comparators for COOR to program (and no message defined for it). COOR includes a Large Tile Count requirement for a Specific Trigger Definition by directly specifying the And-Or Term connected to the Large Tile Fixed Count Threshold Comparator as required in the Specific Trigger Programming. The default value of the programming of all Large Tile Reference Set Threshold Comparators is defined at full scale, thus guaranteeing that Large Tiles not explicitly programmed cannot participate in the Global Count of Tiles above the Large Tile Reference Set. The Keyword "Deallocate" causes TCC to return the specified Reference Set to its default value. 2. Count Thresholds ------------------- a) EM Et Reference Set Count Threshold -------------------------------------- L1CT_Count_Threshold EM_Et_Towers Ref_Set 0 Comparator 1 Value 1 Generic description of the syntax for this command is described in I.4. The Keyword "EM_Et_Towers" is used to identify a count of EM Et Trigger Towers associated with an EM Et Reference Set. There are 4 EM Et Reference Sets, numbered 0 thru 3. The Comparators are numbered from 0 to an upper limit that COOR needs to read from its resource configuration files. The Level 1 Calorimeter Trigger will instrument a minimum of 4 Comparators for each EM Et Reference Set while not necessarily all of these comparison results will be available as Level 1 Framework And-Or Input Terms. The threshold value is specified in direct count of Trigger Towers. The default value of the programming of all EM Et Trigger Tower Count Threshold Comparators is defined at full scale, thus guaranteeing that the resulting And-Or Term default state is negated. b) Tot Et Reference Set Count Threshold --------------------------------------- L1CT_Count_Threshold TOT_Et_Towers Ref_Set 0 Comparator 1 Value 1 Generic description of the syntax for this command is described in I.4. The Keyword "TOT_Et_Towers" is used to identify a count of TOT (i.e. EM+HD) Et Trigger Towers associated with a TOT Et Reference Set. There are 4 TOT Et Reference Sets, numbered 0 thru 3. The Comparators are numbered from 0 to an upper limit that COOR needs to read from its resource configuration files. The Level 1 Calorimeter Trigger will instrument a minimum of 4 Comparators for each TOT Et Reference Set while not necessarily all of these comparison results will be available as Level 1 Framework And-Or Input Terms. The threshold value is specified in direct count of Trigger Towers. The default value of the programming of all TOT Et Trigger Tower Count Threshold Comparators is defined at full scale, thus guaranteeing that the resulting And-Or Term default state is negated. c) Large Tile Reference Set Count Threshold ------------------------------------------- No messages are needed to program Count Thresholds on Global Large Tile Counts. Global Large Tile Counts are compared to three fixed thresholds each, namely ">=1", ">=2", and ">=3". There are 8 Large Tile Counts built from the 8 Large Tile Reference Sets, numbered 0 thru 7. There is thus a total of 24 Large Tile Comparator Outputs from the Level 1 Calorimeter Trigger available as And-Or Terms in the Level 1 Trigger Framework. COOR needs to read from its resource configuration files which and how many of these Level 1 Calorimeter Trigger resources are connected to which And-Or Input Terms of the Level 1 Trigger Framework. 3. Energy Thresholds -------------------- a) Global EM Et Energy Threshold -------------------------------- L1CT_Energy_Threshold EM_Et Comparator 0 Value 55.5 Generic description of the syntax for this command is described in I.4. The Keyword "EM_Et" is used to identify the EM Et Energy Sum carried over the whole detector. The Comparators are numbered from 0 to an upper limit that COOR needs to read from its resource configuration files. The Level 1 Calorimeter Trigger will instrument a minimum of 4 Global EM Et Comparators while not necessarily all (or any) of these comparison results will be available as Level 1 Framework And-Or Input Terms. The threshold value is specified in direct units of GeV. Energy Thresholds accept floating point values. The decimal point is not required for non fractional thresholds. Global EM Et Energy Thresholds will be quanticized by TCC in steps of 1/4 GeV. e.g. a value of 50.6 GeV will be translated into the nearest inclusive value of 50.75 GeV. The default value of the programming of all EM Et Global Energy Threshold Comparators is defined at full scale, thus guaranteeing that the resulting And-Or Term default state is negated. b) Global HD Et Energy Threshold -------------------------------- L1CT_Energy_Threshold HD_Et Comparator 0 Value 55.5 Generic description of the syntax for this command is described in I.4. The Keyword "HD_Et" is used to identify the Global HD Et Energy Sum carried over the whole detector. The Comparators are numbered from 0 to an upper limit that COOR needs to read from its resource configuration files. The Level 1 Calorimeter Trigger will instrument a minimum of 4 Global HD Et Comparators while not necessarily all (or any) of these comparison results will be available as Level 1 Framework And-Or Input Terms. The threshold value is specified in direct units of GeV. Energy Thresholds accept floating point values. The decimal point is not required for non fractional thresholds. Global HD Et Energy Thresholds will be quanticized by TCC in steps of 1/4 GeV. e.g. a value of 50.6 GeV will be translated into the nearest inclusive value of 50.75 GeV. The default value of the programming of all HD Et Global Energy Threshold Comparators is defined at full scale, thus guaranteeing that the resulting And-Or Term default state is negated. c) Global Total Et Energy Threshold ----------------------------------- L1CT_Energy_Threshold TOT_Et Comparator 0 Value 55.5 Generic description of the syntax for this command is described in I.4. The Keyword "TOT_Et" is used to identify the Global TOT (EM+HD) Et Energy Sum carried over the whole detector. The Comparators are numbered from 0 to an upper limit that COOR needs to read from its resource configuration files. The Level 1 Calorimeter Trigger will instrument a minimum of 4 Global EM Et Comparators while not necessarily all of these comparison results will be available as Level 1 Framework And-Or Input Terms. The threshold value is specified in direct units of GeV. Energy Thresholds accept floating point values. The decimal point is not required for non fractional thresholds. Global TOT Et Energy Thresholds will be quanticized by TCC in steps of 1/2 GeV. e.g. a value of 50.6 GeV will be translated into the nearest inclusive value of 51 GeV. The default value of the programming of all TOT Et Global Energy Threshold Comparators is defined at full scale, thus guaranteeing that the resulting And-Or Term default state is negated. d) Global Missing Pt Energy Threshold ------------------------------------- L1CT_Energy_Threshold Miss_Pt Comparator 0 Value 40.0 Generic description of the syntax for this command is described in I.4. The Keyword "Miss_Pt" is used to identify the Missing Pt (a.k.a. Missing Et) Energy Sum carried over the whole detector. For each Trigger Tower the TOT Et Energy is converted (projected) to their x and y components called Px and Py. The arithmetic sum is carried over the whole detector separately for all positive and negative contributions to Px and Py. A signed summation gives the Global Px and Py quantities. A fixed table lookup produces an arithmetic Missing Pt (=SQRT(Px*Px+Py*Py)). A similar programmable lookup is programmed by TCC with the prepared result of the threshold comparison for all values of Px and Py. These lookups provide the near instant computation and threshold comparison of these non-trivial mathematical transformations for each Beam Crossing. The Comparators are numbered from 0 to an upper limit that COOR needs to read from its resource configuration files. The Level 1 Calorimeter Trigger will instrument a minimum of 8 Global Missing Pt Comparators while not necessarily all these comparison results will be available as Level 1 Framework And-Or Input Terms. The threshold value is specified in direct units of GeV. Energy Thresholds accept floating point values. The decimal point is not required for non fractional thresholds. Global TOT Et Energy Thresholds will be quanticized by TCC in steps of 1/2 GeV. e.g. a value of 50.6 GeV will be translated into the nearest inclusive value of 51 GeV. The default value of the programming of all Missing Pt Global Energy Threshold Comparators is defined at full scale, thus guaranteeing that the resulting And-Or Term default state is negated. 4. Excluding One Trigger Tower From All Contributions ----------------------------------------------------- L1CT_Exclude EM_Tower TT_Eta(20) TT_Phi(23) L1CT_Exclude HD_Tower TT_Eta(20) TT_Phi(23) These commands may be used as an emergency protection when one (or more) Trigger Towers becomes noisy and pollutes the trigger signal with a high rate of false events. This gives an emergency protection by forcing to zero the contribution of some Trigger Towers. The energy deposited in the excluded Trigger Towers will stop contributing to all Energy and Momentum sums, Tower Counts, and thus to any subsequent Trigger Decision. The first keyword is "L1CT_Exclude" and introduces this command. The second keyword is "EM_Tower" or "HD_Tower" and targets the EM or HD Tower contribution. The syntax definition to specify individual indices or ranges of Trigger Towers is identical to the syntax allowed in the messages about Reference Sets described in I.2.f. III. L1CT Resources New for Run I ================================= [This section is not written yet, but it is believed none of the new resources will need/accept run-time programming] [Below is a related mail message from Philippe to Jerry] There certainly are new resources for run II, but they are not programmable at run time. e.g.1. the high low-energy cuts used in make quadrant input terms are burnt into the energy lookup PROMs (time scale for change: months, VERY work intensive) e.g.2. the new quadrant matching And-Or terms have their count thresholds fixed, i.e. predefined to say "=1", or ">=1" or ">=2" depending on what fixed thing it is measuring. e.g.3. the Tower Seed Reference Sets (aka. 5th Ref Sets) will be burned in the FPGAs of the cards plugged in the back of our L1CT racks (time scale for change: 1-2 week, not very hard to change) e.g.4. the cryostat rapidity terms are piggy-backing on the existing ref sets and their count thresholds are also going to be hardwired and/or burned into proms. This means the new And-Or Terms will NOT need any additional new programming from COOR. e.g. CEQ(1,q1) will always be on And-Or Term #0 (for example), CEQ(1,q2) on And-Or Term #1 and CEQ(2,q1) will always be on And-Or Term #4 without COOR having to program the 1, the 2, or the q1, or q2 values. The resources that need run time programming (i.e. messages from COOR) are thus essentially the same as for Run I. If you want CEM(1,5GeV) on AO Term #32 (for example) and CEM(2,5GeV) on And-Or Term #33 then COOR will need to program the 5 GeV Ref Set, and the "1" and "2" (or 1 and 2 could be a default/fixed value if we prefer).