Specifications

Configure a Synchronous Serial Interface

IC-72

Cisco IOS Interface Configuration Guide

By default, synchronous interfaces operate in full-duplex mode. To conﬁgure an SDLC interface for

half-duplex mode, use the following command in interface conﬁguration mode:

BSC is a half-duplex protocol. Each block of transmission is acknowledged explicitly. To avoid the

problem associated with simultaneous transmission, there is an implicit role of primary and

secondary station. The primary resends the last block if there is no response from the secondary

within the period of block receive timeout.

To conﬁgure the serial interface for full-duplex mode, use the following command in interface

conﬁguration mode:

Conﬁgure a JT2 6.3-MHz Serial Port Adapter

The JT2 6.3-MHz serial port adapter (PA-2JT2) is available on a second-generation Versatile

Interface Processor (VIP2) in Cisco 7500 series routers and in Cisco 7000 series routers with the

7000 Series Route Switch Processor (RSP7000) and 7000 Series Chassis Interface (RSP7000CI).

The PA-2JT2 port adapter provides two data terminal equipment (DTE) interfaces with coaxial BNC

connectors—one for transmit (TX) and one for receive (RX). This port adapter is compatible with

G.703a allowing communication over a high-speed digital 6.3-MHz (HSD 6.3) leased line service

speciﬁed in ITU Recommendation G.704. The PA-2JT2 port adapter provides the following features

and capabilities:

• Uses bipolar with 8-zero substitution (B8ZS) encoding.

• Supports CRC-16 and CRC-32.

• Operates at 6.312 Mbps, with 50-percent pulse-width B8ZS encoding.

• Provides a ﬁxed clock rate on each JT2 interface port of 6.144 Mbps (not conﬁgurable).

• Provides the functions needed to frame a wideband payload to ITU G.704 and the Nippon

Telegram and Telephone Corporation (NTT)-speciﬁed 6.144-Mbps frame format.

• Designed to conform with the following emissions standards: FCC Class Limits (FCC 47 CFR

Part 15, Subpart B), and EN55022 Class Limits.

• Designed to conform with the following safety standards: UL 1950 D3 Dev., CSA 22.2 No. 950,

and TUV-IEC 950.

To conﬁgure a PA-2JT2 port adapter refer to the “Specify a Synchronous Serial Interface” in this

section.

Conﬁgure PPP

To conﬁgure PPP, see the “Conﬁguring Media-Independent PPP and Multilink PPP” chapter in the

Dial Solutions Conﬁguration Guide.

Command Purpose

half-duplex Conﬁgure an SDLC interface for half-duplex mode.

Command Purpose

full-duplex Specify that the interface can run BSC using switched

RTS signals.