Systech Corporation RCS/5000, Hardware Manual

Page: 22 / 45

Connecting EIA-232 Devices 16
DB-9 Pin
Number
DB-25 Pin
Number/Signal
1 DCD
9 RI
8 CTS
7 RTS
6 DSR
5 GND
4 DTR
3 TX
2 RX
8 DCD
22 RI
5 CTS
4 RTS
6 DSR
7 GND
20 DTR
2 TX
3 RX
Table 3-3: DB-9 to DB-25 Modem Cable
DB-9 Pin
Number
DB-9 Pin
Number
1 DCD
9 RI
8 CTS
7 RTS
6 DSR
5 GND
4 DTR
3 TX
2 RX
4 DTR
9 RI
7 RTS
8 CTS
5 GND
1 DCD
2 RX
3 TX
6 DSR
Table 3-4 DB-9 to DB-9 Terminal Cable
The RCS/6000 does not require the use of all 9 wires. Only the RX, TX, and GND signals are
essential. DTR/DSR and RTS/CTS are only necessary for flow control. RI is only used as a
ring indicator for modem use. Although the RCS/6000 requires DCD by default, you can
change the serial port setting so that the DCD signal is not required. To change the setting,
use the command
set ignoredcd portnumber no i