Perle Systems RIO 5500036-17 - Manual (Page 188)

RIO Remote I/O System User Guide
Installing a Long Distance Module (LDM)
Page 188
Chapter 2 Installing hardware and software
Synchronous X.21 connection
Note
Any connector pins not listed in the next table must not be connected.
DB25 female (LDU) DB15 male (Modem)
Pin Signal Description Pin Signal Description
1 Chassis Chassis ground 1 Chassis Chassis ground
7 GND Ground 8 GND Ground
9 DCD+ Data Carrier Detect 5 Indicate+ Indicate+
10 RXD- Inverse RXD 11 RXD- Inverse RXD
11 RXD+ Receive Data 4 RXD+ Receive Data
12 TXD- Inverse TXD 9 TXD- Inverse TXD
13 TXD+ Transmit Data 2 TXD+ Transmit Data
21 DCD- Data Carrier Detect 12 Indicate- Indicate-
22 DTR+ Data Terminal Ready 3 Control+ Control
23 DTR- Inverse DTR 10 Control- Inverse Control
24 RXC- Inverse RXC 13 Clock- Inverse clock
25 RXC+ Receive Clock 6 Clock+ Clock
Telephone line
DB25 female to DB15
male adaptor.
DB25 female flying lead
to remote site LDU DB25 female flying lead
from host card site LDU
DB25 female to DB15
male adaptor.
X.21
Asynchronous
modem at host
card site X.21
Asynchronous
modem at
remote site