Keithley 2750 User Manual

10-22 Remote Operations Model 2750 Multimeter/Switch System User’s Manual
Table 10-3 provides pinout identification for the 9-pin (DB-9) or 25-pin (DB-25) serial
port connector on the computer (PC).
Error messages
See Appendix C for RS-232 error messages (+800 through +808).
Table 10-2
RS-232 connector pinout
Pin number 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
1
8 CTS, clear to send
1
9 No connection
1
CTS and RTS are not used.
Table 10-3
PC serial port pinout
Signal
DB-9 pin
number
DB-25 pin
number
DCD, data carrier detect 1 8
RXD, receive data 2 3
TXD, transmit data 3 2
DTR, data terminal ready 4 20
GND, signal ground 5 7
DSR, data set ready 6 6
RTS, request to send 7 4
CTS, clear to send 8 5
RI, ring indicator 9 22
2750-900-01.book Page 22 Wednesday, August 3, 2011 7:56 AM

Keithley 2750 Specifications

General

Interface	GPIB, RS-232, Ethernet
Switching Speed	Up to 500 channels/second
Maximum Voltage	300V
Operating Temperature	0°C to 50°C
Measurement Functions	DCV, ACV, DCI, ACI, 2-wire Resistance, 4-wire Resistance, Frequency, Temperature
Resolution	6.5 digits
Current	1A
Maximum Current	1A