78 Appendix A Technical specificationsNN46110-316 02.01Figure 28 Modem cable (9-pin D-sub plug to RS-232-C modem plug)Table 19 provides the multiple DB9/DB25 serial interface cable pinouts.Modem cable specificationsIf you need to connect a modem to a VPN Router 1750, you must obtain anappropriate modem cable. The modem cable must have a 9-pin D-sub plug thatconnects to the VPN Router 1750 serial port and a 25-pin D-sub plug thatconnects to the RS-232-C modem port (Figure 29).Table 19 Multiple DB9 and DB25 connector pinoutsSerial portDB9 connectorSerial portDB25 connectorSerial portDB25 connectorSerial portDB9 connectorPinout Signal Pinout Signal Pinout Signal Pinout Signal2 RXD 3 TXD > 2 RXD 3 TXD3 TXD 2 RXD > 3 TXD 2 RXD4 DTR 20 DSR > 6 DTR 6 DSR5 Ground 7 Ground > 7 Ground 5 Ground6 DSR 6 DTR > 20 DSR 4 DTR7 RTS 4 RTS > 5 CTS 8 CTS8 CTS 5 CTS > 4 RTS 7 RTSPin 1Pin 5Pin 6Pin 910 ft(3.05 m)9-position D-sub receptacle with screw locks(ground shield connected to backshell)CAB0056APin 13Pin 1Pin 25Pin 1425-position D-sub plug with screw locks(ground shield connected to backshell)
