Connectors, Cables, and Pin Assignments
C-7
9820-A2-GB20-20
June 2000
X.21 Network Cable (Models 9820, 9820-2M, 9820-8M)
This cable is used to connect the network data port to an NTU with an X.21
interface. It is a 25-position EIA-530A-to-15-pin X.21 (DB25-to-X.21) cable.
This cable (Part No. 035-0384-1031) is part of the X.21 Cable Kit (Feature No.
9008-F1-521).
99-16303
The following table provides the pin assignments for the DB25-to-X.21 network
cable.
Signal
ITU #
25-Pin
Socket
Pin #
Direction
15-Pin
Plug
Pin #
Transmit Data (TXD) 103 2 (A)
14 (B)
To DCE 2 (A)
9 (B)
Received Data (RXD) 104 3 (A)
16 (B)
From DCE 4 (A)
11 (B )
Request to Send (RTS) 105 4 (A)
19 (B)
To DCE 3 (A)
10 (B)
Signal Ground/Common (SG) 102 7 — 8
Data Channel Received Line
Signal Detector (RLSD or LSD)
109 8 (A)
10 (B)
From DCE 5 (A)
12 (B)
Transmit Signal Element/
Terminal Timing (TT) —
DTE Source
113 24 (A)
11 (B)
To DCE 7 (A)
14 (B)
Received Signal Element Timing
(RXC) — DCE Source
115 17 (A)
4 (B)
From DCE 13 (A)
3 (B)