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Quidway® NetEngine 20 Routers Synchronous Serial Port Module
Copyright ©2007 Huawei Technologies Co., Ltd. All rights reserved.
http://www.huawei.com/products/datacomm/
1
Quidway® NetEngine 20 Routers Synchronous Serial Port Module
Overview
The synchronous serial port module (4SAE) of an NE20 router implements the sending, receiving
and processing of synchronous serial port data stream. It supports data terminal equipments (DTE)
and data circuit-terminating equipments (DCE).
A synchronous serial po rt can work in the DTE or DCE mode. Two devices directly connected must
work respectively in the DTE and DCE modes. The DCE provides the synchronization clock and
assigns communication rate, while the DTE receives the synchronization clock and communicates
according to the assigned baud rate.
Electrical signal standards and baud rates supported by a synchronous serial port varies with the
working mode. The maximum transmission distance of signals depends on the baud rate and cabl e.
Refer to the table below for the mapping between cable, baud rate and the maximum transmission
distance of signals.
V.24 V.35
Baud rate
(bit/s)
Maximum transmission
distance (m)
Baud rate
(bit/s)
Maximum transmission
distance (m)
2400 60 2400 1250
4800 60 4800 625
9600 30 9600 312
19200 30 19200 156
38400 20 38400 78
64000 20 56000 60
115200 10 64000 50
- - 2048000 30
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Quidway® NetEngine 20 Routers Synchronous Serial Port Module
Copyright ©2007 Huawei Technologies Co., Ltd. All rights reserved.
http://www.huawei.com/products/datacomm/
2
At present, the NE20E router provides only one type of synchronous serial port module, namely
4-port enhanced high-speed synchronous serial port card.
Specifications
Specifications of the synchronous serial port module are described as below.
Module Interface type Description
RT-FIC-4SAE DB-28
A 4-port enhanced synchronous/asynchronous
interface module
Cable
DB-28
V.24 DTE cable
V.24 DCE cable
V.35 DTE cable
V.35 DCE cable
V.21 DTE cable
X.21 DCE cable
RS449 DTE cable
RS449 DCE cable
RS530 DTE cable
RS530 DCE cable