Specifications

C-20 Cisco Multiport Router Installation and Configuration Guide
Synchronous Serial Cable Assemblies and Pinouts
X.21
Figure C-10 shows the X.21 cable assembly. Table C-13 lists the DTE pinouts. Table C-14
lists the DCE pinouts. Arrows indicate signal direction: —> indicates DTE to DCE, and
<— indicates DCE to DTE.
Figure C-10 X.21 Cable Assembly
J1-18
J1-17
TxD/RxD+
TxD/RxD–
Twisted pair no. 1 —>
—>
J2-R
J2-T
RD+
RD–
J1-26
J1-25
RxC/TxCE+
RxC/TxCE–
Twisted pair no. 4 <—
<—
J2-U
J2-W
SCTE+
SCTE–
J1-22
J1-21
NIL/RxC+
NIL/RxC–
Twisted pair no. 3 —>
—>
J2-V
J2-X
SCR+
SCR–
J1-20
J1-19
TxCE/TxC+
TxCE/TxC–
Twisted pair no. 2 —>
—>
J2-Y
J2-AA
SCT+
SCT–
Table C-12 V.35 DCE Cable Pinouts (DB-60 to 34-Pin) (Continued)
60 Pin Signal Description Direction 34 Pin Signal
H1974
60-pin connector (J1)
15-pin connector (J2)
Connectors are not to scale
J2-8
J2-15
J2-9
J2-1
J1-46
J1-45
J1-16
J1-15
J1-1
J1-30
J1-31
J1-60