Connecting a
Modem
Configuring the
Serial Console Port
as a PPP Console
In order to use the serial console port as a PPP console, you must connect a modem to the switch. When you use the specified serial cable and connectors, the switch will convert the normal DCE interface to a DTE interface that is used by modems.
When the switch is configured for PPP mode, it will periodically send the modem config string from the serial console port. This will synchronize the baud rates between the modem and the console port and configure the modem to operate with the switch’s DTE interface.
The switch does not use any output signals except for TXD. It uses the DTR (converted to DSR by the specified cable and connectors) input connected to the modem DCD output, to detect that the modem is connected. It supports XON/XOFF flow control (or none).
To connect a modem:
1.Attach a
2.Attach the
Figure 17. Typical Connection Between the Switch and a Modem
Typical Connection between Cajun
Switch and Modem
DB25 M - RJ45 | Pin 2 - TXD |
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P/N 38210003 | Pin 3 | - RXD |
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| Pin 7 | - GND |
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Modem
Cajun Switch
You can reconfigure the console serial port as a PPP Console to support a
*Note: The lack of an IP address for the PPP serial interface causes the switch to immediately return to sending the modem configuration string. Typing TTY will
Cajun P880 Routing Switch Installation Guide | 2 - 31 |