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Link Interfaces Reference
3-4 — Orbitor 3000 Reference Manual
V.11 & X.21 Link Pinouts
The connector shown here and pinouts described here correspond to
the connector labeled “V.11/X.21” on the back of the Orbitor 3000.
1
8
9
15
DB15 Female DTE
Contact
Number
X.21
Circuits
Reference
Circuit
Name
Direction
To From
DCE DCE
1
Protective Ground
NA
2
T (A)
Transmitted Data (A)
X
3
C (A)
Control (A)
X
4
R (A)
Received Data (A)
X
5
I (A)
Indication (A)
X
6
S (A)
Signal Element Timing (A)
X
7
----------
8
Ground
Signal Ground
NA
9
T (B)
Transmitted Data (B)
X
10
C (B)
Control (B)
X
11
R (B)
Received Data (B)
X
12
I (B)
Indication (B)
X
13
S (B)
Signal Element Timing (B)
X
14
----------
15
----------
Figure 3—5 V.11 Link Pinouts
The connecting cable must be a shielded cable.
Circuits which are paired (contain an (A) and (B) reference) should be connected to twisted pairs within the
connecting cable.
NOTE For U.K. Approval:
The connecting cable should be manufactured from Belden Cable, or a cable with equivalent specifications. Each end
must be terminated in a male 15 pin X.21 connector as defined in ISO-4903 1989, but one end of the cable must have
UNC-4-40 screws and the other end must have M3 screws. The cable may be any length between 0 and 5M.