Keithley 2701

10-32 Remote Operations Model 2701 User’s Manual
RS-232 connections
The RS-232 serial port is connected to the serial port of a computer using a straight-
through RS-232 cable terminated with DB-9 connectors. Do not use a null modem cable.
The serial port uses the transmit (TXD), receive (RXD), ready to send (RTS), clear to send
(CTS), and signal ground (GND) lines of the RS-232 standard. Figure 10-11 shows the
rear panel connector for the RS-232 interface and Table 10-4 shows the pinout for the
connector.
If your computer uses a DB-25 connector for the RS-232 interface, you will need a cable
or adapter with a DB-25 connector on one end and a DB-9 connector on the other, wired
straight through (not null modem).
Figure 10-11
RS-232 interface connector
Table 10-4
RS-232 connector pinout
Pin # Description
1 No connection
2 TXD, transmit data
3 RXD, receive data
4 No connection
5 GND, signal ground
6 Not used
7 RTS, ready to send
8 CTS, clear to send
9 No connection
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Rear Panel Connector