Isotech TTI-7-R, Operator'S Handbook Manual

Page: 72 / 120

Options and accessories
7.3.1 The RS-232 Connector
RS-232 connection is via a 9-way (socket) D-type connector on the
back panel as shown in Figure 7.2.
Figure 7.2 - RS-232 Connector
View towards rear panel
RS232 connector
=Not
connected on
TTI-7-R
7.3.2 Pin Connections
Computer TTI-7-R
25-Pin
Connector 9-Pin
Connector
Function
9-Pin
Connector
Function
3 2 Rx 3 Tx
2 3 Tx 2 Rx
7 5 GND 5 GND
DSR
6*
4*
6*
7*
RTS
8 CTS
5 8 CTS 7 RTS
* Pins must be linked
To make an RS232 connection, use fully screened cable
assemblies to maintain EMC integrity. A 5-wire (TXD, RXD, GND,
RTS, CTS) cross over cable is recommended.
Three wire connection (TXD, RXD, GND) is not recommended, but
may be implemented by connecting RTS and CTS together at the
TTI-7-R end. In this case, the DTE must not send characters too
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