3Com 3032 Configuration Manual page 131

Enable level detection for the synchronous serial
interface.
Disable level detection for the synchronous serial
interface.
Level detection is enabled for the synchronous serial interface by default.
9 Enable or disable data carrier detection
By default, when the system decides whether the synchronous serial interface is in
UP status or DOWN status, it detects the DSR signal, DCD signal and whether the
interface connects a cable at the same time. Only when the three signals are
effective, will the system regard the interface is in UP status, otherwise, in DOWN
status. If data carrier detection is disabled for the synchronous serial interface, the
system will not detect the DCD signal.
Please use the following commands in the view of the synchronous serial
interface.
Table 118 Enable or disable data carrier detection for the synchronous serial interface
Operation
Enable data carrier detection for the synchronous serial
interface.
Disable data carrier detection for the synchronous serial
interface.
Data carrier detection is enabled for the synchronous serial interface by default.
10 Set the synchronous serial interface to work in full duplex or half duplex mode
To operate with some devices working in half-duplex mode, the synchronous serial
interface can be configured to work in half-duplex mode.
Please make the following configurations in synchronous serial interface mode.
Table 119 Set the synchronous serial interface to work in full duplex or half duplex mode
Operation
Set the synchronous serial interface to work in half
duplex mode
Set the synchronous serial interface to work in full
duplex mode
By default, the synchronous serial interface works in full duplex mode.
11 Enable or disable internal loopback/external loopback
To perform special function test, the internal loopback/external loopback are
enabled for the synchronous serial interface.
Please use the following commands in the view of the synchronous serial
interface.
Table 120 Enable/disable internal loopback/external loopback for the synchronous serial
interface
Operation
Enable the internal loopback/external loopback for
the synchronous serial interface.
Disable the internal loopback/external loopback
for the synchronous serial interface.
The internal loopback/external loopback are disabled by default.
Synchronous Serial Interface
detect dsr-dtr
undo detect dsr-dtr
Command
detect dcd
undo detect dcd
Command
reverse-rts
undo reverse-rts
Command
loopback
undo loopback
127