CARDS AND CONNECTIONS REQUIRED FOR A TIER 3 BACKPLANE
            (does not show connections to IMLRO/TRIGGER FRAMEWORK)
         
                                                                21-JAN-1992 

    BOARD       TREE            REF SET/        THR     TIMING 
    TYPE        TYPE            LOOKUP          ESH     SIGNAL
    -----       ----            --------        ----    ------

15. CAT2   >--- Tot Counter     Ref Set 3       0..3    16 (CNT OP CLK TIER 3)
14. CAT2   >--- Tot Counter     Ref Set 2       0..3    16
13. CAT2   >--- Tot Counter     Ref Set 1       0..3    16
12. CAT2   >--- Tot Counter     Ref Set 0       0..3    16

11. CAT2   >--- EM  Counter     Ref Set 3       0..3    16 
10. CAT2   >--- EM  Counter     Ref Set 2       0..3    16
9.  CAT2   >--- EM  Counter     Ref Set 1       0..3    16
8.  CAT2   >--- EM  Counter     Ref Set 0       0..3    16
               
25. CAT3   >-.- HD  Adder       First LU       12..15   19 (EN OP CLK T3 LU1)
24. CAT3     |- HD  Adder       First LU        8..11   19
23. CAT3     |- HD  Adder       First LU        4..7    19
22. CAT3     |- HD  Adder >---. First LU        0..3    19
             |                |
21. CAT3     `- HD  Adder >-. | Second LU       0..3    20 (EN OP CLK T3 LU2)
                            | |
         .-----<---------<--' |
         |.----<---------<--. |
         |                  | |
20. CAT3 | >-.- EM  Adder >-' | Second LU       0..3    20 (EN OP CLK T3 LU2) 
         |   |                |
19. CAT3 |   |- EM  Adder     | First LU       12..15   19 (EN OP CLK T3 LU1)
18. CAT3 |   |- EM  Adder     | First LU        8..11   19 
17. CAT3 |   |- EM  Adder     | First LU        4..7    19 
16. CAT3 |   `- EM  Adder >-. | First LU        0..3    19
         |                  | |
         | .---<---------<--' |
         | |.--<---------<----'
         | |                   
5.  CAT3 | `-.- Tot Adder       First LU        8..11   21 (TOT OP CLK T3 LU1)
4.  CAT3 |   |- Tot Adder       First LU        4..7    21
3.  CAT3 |   `- Tot Adder       First LU        0..3    21
         |                     
2.  CAT3 `----- Tot Adder       Second LU       0..3    22 (TOT OP CLK T3 LU2)
                               
27. CAT3   >--- Py  Adder >---.                         27 (MOM OP CLK T3)
                              |
26. CAT3   >--- Px  Adder >-. |                         27
                            | |
         .-----<---------<--' |
         |-----<---------<----'
         |   
7.  FMLN `---.- Missing Pt Thresh. Comp.        0..7    28 (FMLN CLOCK)
6.  FMLN     `- Missing Pt Direct Lookup                28
 
1.  CTMBD