Specifications

5-15
PA-8T-V.35 Synchronous Serial Port Adapter Installation and Configuration
OL-3563-03
Chapter 5 Configuring the PA-8T-V.35 Interfaces
Configuring Half-Duplex and Binary Synchronous Communications
For command descriptions, refer to the Configuration Fundamentals Configuration Guide publication.
For more information, see the “Obtaining Documentation” section on page x and the “Obtaining
Technical Assistance” section on page xi.
Note If you are configuring a PA-8T-V.35 on a Cisco 7200 series router and you want to configure the interface
for half-duplex or Binary Synchronous Communication Protocol (Bisync) operation, proceed to the next
section “Configuring Half-Duplex and Binary Synchronous Communications”; otherwise, proceed to the
“Checking the Configuration” section on page 5-17.
Configuring Half-Duplex and Binary Synchronous
Communications
This section explains how to configure PA-8T-V.35 interfaces for half-duplex and Bisync operation in
Cisco 7100 series and Cisco 7200 series routers.
Note Cisco IOS Release 11.2(7a)P or later supports half-duplex and Bisync operation on PA-8T-V.35
interfaces installed in Cisco 7204 and Cisco 7206 routers.
Cisco IOS Release 11.1(19)CC1 or later or 11.3(4)AA or later supports half-duplex and Bisync
operation on PA-8T-V.35 interfaces installed in Cisco 7202 routers.
Cisco IOS Release 12.0(3)T or later or 12.0(2)XE or later supports half-duplex and Bisync operation on
PA-8T-V.35 interfaces installed in Cisco 7204VXR and Cisco 7206VXR routers.
The Catalyst RSM/VIP2, Catalyst 6000 family FlexWAN module, Cisco uBR7200 series routers, and
VIP do not support half-duplex and Bisync operation on PA-8T-V.35 port adapters.
Use the half-duplex command to configure PA-8T-V.35 interfaces for half-duplex mode; full-duplex
mode is the default for low-speed serial interfaces. Serial DCE interfaces in half-duplex mode can be
configured for controlled-carrier mode or constant-carrier mode; constant-carrier mode is the default.
Controlled-carrier mode sets the PA-8T-V.35 interface to deactivate data carrier detect (DCD) until a
transmission is sent to the interface. After a transmission is received, DCD is activated and the interface
waits a user-configured amount of time and then transmits the data. After the transmission, the interface
waits a user-configured amount of time and then deactivates DCD. Constant-carrier mode activates DCD
at all times.
Use the half-duplex controlled-carrier command to configure a PA-8T-V.35 interface for
controlled-carrier mode. Use the no half-duplex controlled-carrier command to return the interface to
constant-carrier mode.
Follow these steps to configure controlled-carrier mode on a PA-8T-V.35 interface:
Step 1 At the privileged-level prompt, enter configuration mode and specify that the console terminal is the
source of the configuration subcommands, as follows:
Router# configure terminal
Enter configuration commands, one per line. End with Crtl-Z.
Router(config)#