Cisco Systems C819HG4GVK9, C819GUK9 Specifying a Synchronous Serial Interface, Command, Purpose

Chapter 8 Configuring the Serial Interface

How to Configure Serial Interfaces

•Configuring Half-Duplex and Bisync for Synchronous Serial Port Adapters on Cisco 819 ISRs, page 8-8(Optional)

•Configuring Compression of HDLC Data, page 8-9(Optional)

•Using the NRZI Line-Coding Format, page 8-9(Optional)

•Enabling the Internal Clock, page 8-10(Optional)

•Inverting the Transmit Clock Signal, page 8-10(Optional)

•Setting Transmit Delay, page 8-11(Optional)

•Configuring DTR Signal Pulsing, page 8-11(Optional)

•Ignoring DCD and Monitoring DSR as Line Up/Down Indicator, page 8-11(Optional)

•Specifying the Serial Network Interface Module Timing, page 8-12(Optional)

See the “Configuration Examples” section on page 8-19for examples of configuration tasks described in this chapter.

Specifying a Synchronous Serial Interface

To specify a synchronous serial interface and enter interface configuration mode, use one of the following commands in global configuration mode.

Command	Purpose
Router(config)# interface serial 0	Enters interface configuration mode.

Specifying Synchronous Serial Encapsulation

By default, synchronous serial lines use the High-Level Data Link Control (HDLC) serial encapsulation method, which provides the synchronous framing and error detection functions of HDLC without windowing or retransmission. The synchronous serial interfaces support the following serial encapsulation methods:

•HDLC

•Frame Relay

•PPP

•Synchronous Data Link Control (SDLC)

•SMDS

•Cisco Serial Tunnel (STUN)

•Cisco Bisync Serial Tunnel (BSTUN)

•X.25-based encapsulations

To define the encapsulation method, use the following command in interface configuration mode.

Command			Purpose
Router(config-if)#encapsulation {hdlc frame-relay			Configures synchronous serial encapsulation.
	ppp	sdlc-primary sdlc-secondary smds stun
	x25	bstun}

Cisco 819 Series Integrated Services Routers Software Configuration Guide

OL-23590-02 8-7