3Com 3032 Configuration Manual page 129

Perform following commands in synchronous serial interface view.
Table 112 Set the digital signal encoding format of synchronous serial interface
Operation
Using NRZI encoding format
Using NRZ encoding format
By default, the digital signal encoding format of synchronous serial interface is
NRZ.
5 Set baud rate
Please use the following command in the view of the synchronous serial interface.
Table 113 Set the baud rate of synchronous serial interface
Operation
Set baud rate of the synchronous serial
interface
When two synchronous serial interfaces are connected, the baud rate on line is
determined at DCE-side. Therefore, when the synchronous serial interfaces are
working in DCE mode, the baud rate is to be set. However, if the interfaces act as
DTE, then the baud rate need not be configured. Default baud rate of
synchronous serial interface is 64000 bps.
After the synchronous/asynchronous serial interface is set to synchronous mode
from asynchronous mode, the system will automatically change the default baud
rate to 64000 bps.
6 Select work clock
The synchronous serial interface works in two modes: DTE and DCE. Different
working modes have different working clocks.
If the synchronous serial interface is used as DCE, it is necessary to provide
clock to the opposite DTE by choosing DCEclk.
If the synchronous serial interface is used as DTE, the clock provided by the
opposite DCE needs to be accepted. As the receiving clock and transmitting
clock of the synchronous equipment are independent, the receiving clock of
DTE can be the transmitting clock or receiving clock of DCE or the sending
clock of DTE can be the transmitting clock or receiving clock of DCE. Thus,
there will be four combinations, i.e. four kinds of clock selections are available
at DTE side.
Figure 46 Schematic diagram of synchronous serial interface clock selection
Table 114 Selection method with synchronous serial interface serving as DTE-side clock
Selection method
Command
code nrzi
undo code
Command
baudrate baudrate
TxClk
DCE
RxClk
Meaning
Synchronous Serial Interface
DTE
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