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Interface Signals
B-4
SpectraComm 553 Fractional T1 DSU
076R155-000
Installation and Operation Manual
Issue 7
Table B-6
Cascade Port and Station Clock Signal Assignments – SpectraComm Shelf
with 50-pin Connector Back Panel (Connectors J20 – J22)
Signal
(Slot 1) J20
(Slot 2) J20
(Slot 3) J20
(Slot 4) J20
Cascade Send Data (Ring)
1
5
9
13
Cascade Send Data (Tip)
26
30
34
38
Station Clock A
2
6
10
14
Cascade Receive Data (Ring)
3
7
11
15
Cascade Receive Data (Tip)
28
32
36
40
Station Clock B
27
31
35
39
Signal
(Slot 5) J20
(Slot 6) J20
(Slot 7)J21
(Slot 8) J21
Cascade Send Data (Ring)
17
21
1
5
Cascade Send Data (Tip)
42
46
26
30
Station Clock A
18
22
2
6
Cascade Receive Data (Ring)
19
23
3
7
Cascade Receive Data (Tip)
44
48
28
32
Station
Clock
B
43 47 27 31
Signal
(Slot 9) J21
(Slot 10) J21
(Slot 11) J21
(Slot 12) J21
Cascade Send Data (Ring)
9
13
17
21
Cascade Send Data (Tip)
34
38
42
46
Station Clock A
10
14
18
22
Cascade Receive Data (Ring)
11
15
19
23
Cascade Receive Data (Tip)
36
40
44
48
Station
Clock
B
35 39 43 47
Signal
(Slot 13) J22
(Slot 14) J22
(Slot 15) J22
(Slot 16) J22
Cascade Send Data (Ring)
1
5
9
13
Cascade Send Data (Tip)
26
30
34
38
Station Clock A
2
6
10
14
Cascade Receive Data (Ring)
3
7
11
15
Cascade Receive Data (Tip)
28
32
36
40
Station Clock B
27
31
35
39