3onedata MODEL7302 Посібник користувача - Сторінка 8

Переглянути онлайн або завантажити pdf Посібник користувача для Модем 3onedata MODEL7302. 3onedata MODEL7302 10 сторінок. Fe1 optic fiber modem

5.3 Settings of Switch and Jumper

Independent device has totally 5 setting switches, with S5 located on the rear panel and

S1~S4 under the bottom cover. The user can easily make settings without the need to open the

cover.

E1 interface timing (S5.1=ON/OFF, S5.2=OFF): the sending timing is E1 port timing, and

the received data, after buffering, is synchronized with E1 port timing.

Optic interface receiving timing (optic interface originated from the clock, S5.1=OFF，

S5.2=ON):

the sending timing is optic interface receiving timing, and the received data, after buffering, is

synchronized with optic interface receiving timing. Under this timing mode, local time slot

setting can automatically track the opposite time slot setting.

Local main timing (S5.1=ON, S5.2=ON): the sending timing is of local crystal oscillation,

and the received data, after buffering, is synchronized with local timing.

S5.5～S5.8 of coded switch S5 are used for setting the loop back test and pseudo-random

code test. S5.5 is local loop back control （LLOOP） and optic interface is directly looped back

to E1

interface. "OFF" indicates normal operation; "ON" indicates local loop back

test. The default is "OFF". It is used for testing whether local device is in normal operation.

S5.6: local digital loop back control (DLOOP). "OFF" indicates normal operation; "ON"

indicates local digital loop back. The default is "OFF". With a loop back from local E1

interface to optic interface, it is used for testing whether the remote device and optic

line are in normal operation.

S5.7: "OFF" indicates normal operation；"ON" indicates command remote loop back. The

default is "OFF". As this command must be sent through E1 line to remote end for

validness, it will become invalid at the following two cases: ① the remote end is not

FE1 Fiber Modem remote device; ② FE1 Fiber Modem is working at a non-framing

status, at this moment all time slots of E1 are used for data transmission at a rate of

2048Kbps. Through a sending of loop back command from local device to remote

device, the command remote loop back is achieved.

FE1 Fiber Modem

Local Loop back Schematic

FE1 Fiber Modem

Local Digital Loop back

Page 8 of 10

MODEL7302 User Manual

Optical

Interface

Optical

Interface