Level 1 (and 2) Trigger Framework Test Rack Cabling --------------------------------------------------- Original: 23-MAR-1999 Revised: 20-JUL-1999 This file describes details of cabling for the Level 1 (and Level 2) Trigger Framework Test Rack at MSU. **** Front Cables for the L1 Framework and Scaler/L2 FW Test Rack **** 1. 2 THE Cards, each with 64 outputs, feeding an adjacent Pass-Through This is the most common front cabling arrangement in the L1 Trigger Framework. It is also seen in the Test Rack, although frequently it is reduced to 1 THE Card feeding half of an adjacent Pass-Through. Eight (four), 34-conductor cables with a single female connector on each end are required for a full (half) set. The 2 THE Cards are positioned such that the card closest to the Pass-Through feeds the P2-related Pass-Through connectors, and the card furthest from the Pass-Through feeds the P3-related connectors. This tries to equalize the cable-length by trading horizontal vs. vertical displacement. With this arrangement, the cabling required here is as follows: Qty Type # sections cut style note --- ---- ---------- --------- ---- 2 18" 1 nominal PT MSA_In(63:32) 6 18" 1 maximal all other MSA_In If only 1 THE Card is used, the following cabling is required: Qty Type # sections cut style note --- ---- ---------- --------- ---- 2 18" 1 nominal PT MSA_In(63:32) 2 18" 1 maximal all other MSA_In This arrangement is found in the following locations in the L1 Trigger Framework: And-Or Input TRM's 2 sets Physics And-Or Fired AONM's 2 half sets Geo Sect FE Bz TRM's 1 half set Sp Trig Mask to L2 FIFO TRM's 1 half set Individual ST Disable TRM's 1 set L2 Accept per Sp Trig 1 half set L2 Reject per Sp Trig 1 half set -------- 6 sets = 48 cables 2. Two TDM's feeding one Pass-Through The 2 TDM's each provide 16 signals (1 34-conductor cable) from their MSA 15:0 outputs to the Pass-Through. Two 34-conductor cables with a single female connector on each end are required. Again, the TDM's are positioned to trade horizontal and vertical displacement, to try to equalize cable lengths. The cabling here is as follows: Qty Type # sections cut style note --- ---- ---------- --------- ---- 1 18" 1 maximal ST 15:0 1 24" 1 minimal * ST 31:15 * or nominal 3. Additional cards on Specific Trigger Fired Bus There is 1 FOM and an FOM++ on the Specific Trigger output bus which feed NON-adjacent Pass-Through cards. The single FOM++ has 3 intervening cards, while the FOM has 4 intervening slots. Eight, 34-conductor cables with a single female connector on each end are required. The cabling is as follows: Qty Type # sections cut style note --- ---- ---------- --------- ---- 4 24" 1 minimal * FOM++ 4 24" 1 nominal FOM * or nominal 4. Exp Group Enable, EG FE Bz Disable, Global Disable signals The 2 Exposure Group Partial Enable AONM's, plus 1 Exposure Group Front-End Busy FOM, plus the Global Disable TRM, all must feed: 1. The 2 TDM's 2. The Exposure Group Per-Bunch Scalers All of this is done using a single Pass-Through, located directly to the left of the 8 TDM's. The following Pass-Through connectors are used: MSA Usage --- ----- 15:0 31:16 Exp Group Partial Enable to EG PBS's 47:32 63:48 Exp Group Partial Enable to TDM's 79:64 95:80 EG FE Bz, Glob Disable to EG PBS's 111:96 127:112 EG FE Bz, Glob Disable to TDM's Four, 34-conductor cables are required for this purpose. These cables have a single female connector on ONE end, but the other end is split, with two (34-pin) female connectors on each "half", allowing two cards to drive a single cable. The cabling is as follows: Qty Type # sections cut style note --- ---- ---------- --------- ---- 4 18" 3 nominal split end 5. All Common Signals to the SCL Hub End More on this to come... **** Rear Cables in the L1 Framework Rack **** 1. Physics Partial And-Or Fired to TDM's The 2 Physics And-Or Fired Pass-Throughs each provide 64 signals (16 to each of the 2 TDM's). A total of 4, 34-conductor cables are required. These cables have a single 34-pin female connector on the Pass-Through end, and split into 2, 16-conductor female connectors (one goes to P2 and the other to P3, both in the same slot). These cables need to do some criss-crossing, as both Pass-Throughs provide one cable for each of the 2 TDM's. The cables are all identical, and are as follows: Qty Type # sections cut style note --- ---- ---------- --------- ---- 4 18" 2 nominal split end 2. Exp Group Enable, EG FE Bz Disable, Global Disable signals Recall that (separate copies of) these signals feed 2 destinations (the TDM's and the PBS's, see above). They enter the back of the rack via a Pass-Through directly adjacent to the TDM chain. NO Rear Paddleboard is used on this Pass-Through. Two cables are required to provide these signals to the TDM chain. In principle these cables are short and simple. In practice, since no Rear Paddleboard is used, and there are issues of order/polarity swapping (see CABLE_NOTES.TXT), these cables are made from individual twisted-pair material made into a harness. This is also useful for the Global Disable signals, allowing us to mix in the Skip Next Tick signal (from the FOM++) as a Global Disable. Two additional cables are required to provide these signals to the PBS chain. These are just copies of the above cables, and two 34-conductor twist'n'flat cable (with a MALE extension-type end connector on one end) are used to provide the "long haul" to the scalers. The cables are therefore as follows: Qty Type # sections cut style note --- ---- ---------- --------- ---- 4 individual twisted-pair material 2 18" 1 nominal 1 male end req'd 3. L2 ST Fired Mask to L2 Framework These cables go from the L2 ST Fired Mask Pass-Through to two separate AONMs. Four cables are required, each of which must visit both AONMs. This is problematic, as the AONM are not all adjacent, so we can't use just a single "stack" of Rear Paddleboards. Once each cable needs to drop off to 2 Rear Paddleboards, a lot of criss-crossing is required. Each cable must have 1 34-conductor female connector on one end, and 2 34-conductor female connectors on 2 different flat sections near the other end. They are identical, and are as follows: Qty Type # sections cut style note --- ---- ---------- --------- ---- 4 24" 3 total nominal 4. Individual Disables from Pass-Throughs to TDM's These cables are identical to the Physics AO Fired-to-TDM cables. Qty Type # sections cut style note --- ---- ---------- --------- ---- 4 18" 2 nominal split end **** Timing Signal Generation **** In the absence of a Master Clock, the first 8 timing signals are provided by Big Ben and are available as P5(7:0). These signals are connected to the TOM using a standard timing cable (individual twisted pair as opposed to twist and flat). P5(8) is a copy of the Tick Clock which is phase shifted for use by the Helper Function. It is connected to MSA_Input(51) of the Helper Function via a rear paddle board with terminating resistors. The Helper Function provides timing signals (15:8) as MSA_Outputs (7:0). These signals are also connected to the TOM using a twisted pair cable. Note, however, that a standard timing cable is not sufficient. Typically, a timing cable groups the timing signals 4:0, 7:5, 13:9, and 8, 15:14. In the case of the Helper Function case, the timing signals appear on the cable as 7:0 but in fact drive 15:8 on the TOM. Thus a special cable is needed in which the timing signals are grouped 5:1 and 0, 7:6. Once the timing signals are on the backplane, a P1->P5 Copier is used with a standard timing cable to drive the timing signals on the crates under test. Note that the timing in the crate in which the Big Ben and Helper Function are located will be different so that it is preferable to have a completely separate timing crate.