S1-2 and S1-3 CLOCK MODES

Set switch S1-2 and S1-3 to determine the 2701RC’s transmitter timing.

S1-2

S1-3

Clock Mode

On

On

Network (Recieved Recovered)

Off

On

Internal

On

Off

External

Off

Off

Network (Recieved Recovered)

 

 

 

Network Clock Transmitter timing is derived using the received line signal (received recovered) from the network.

Internal Clock Transmitter timing is derived from an internal clock source.

External Clock Transmitter timing is derived from DTE terminal tim ing.

SWITCH S1-4 THROUGH S1-8: DTE DATA RATE

Use switches S1-4 through S1-8 to set the DTE data rate.

S1-4

S1-5

S1-6

S1-7 S1-8

Speed

ON

OFF

OFF

OFF

OFF

64kbps

OFF

ON

OFF

OFF

OFF

128kbps

ON

ON

OFF

OFF

OFF

192kbps

OFF

OFF

ON

OFF

OFF

256kbps

ON

OFF

ON

OFF

OFF

320kbps

OFF

ON

ON

OFF

OFF

384kbps

ON

ON

ON

OFF

OFF

448kbps

OFF

OFF

OFF

ON

OFF

512kbps

ON

OFF

OFF

ON

OFF

576kbps

OFF

ON

OFF

ON

OFF

640kbps

ON

ON

OFF

ON

OFF

704kbps

OFF

OFF

ON

ON

OFF

768kbps

ON

OFF

ON

ON

OFF

832kbps

OFF

ON

ON

ON

OFF

896kbps

ON

ON

ON

ON

OFF

960kbps

OFF

OFF

OFF

OFF

ON

1024kbps

ON

OFF

OFF

OFF

ON

1088kbps

OFF

ON

OFF

OFF

ON

1152kbps

ON

ON

OFF

OFF

ON

1216kbps

OFF

OFF

ON

OFF

ON

1280kbps

ON

OFF

ON

OFF

ON

1344kbps

OFF

ON

ON

OFF

ON

1408kbps

 

 

 

 

7

 

ON

ON

ON

OFF

ON

1472kbps

OFF

OFF

OFF

ON

ON

1536kbps

ON

OFF

OFF

ON

ON

1600kbps

OFF

ON

OFF

ON

ON

1664kbps

ON

ON

OFF

ON

ON

1728kbps

OFF

OFF

ON

ON

ON

1792kbps

ON

OFF

ON

ON

ON

1856kbps

OFF

ON

ON

ON

ON

1920kbps

ON

ON

ON

ON

ON

1984kbps

OFF

OFF

OFF

OFF

OFF

Clear Channel 2048kbps

NOTE: When the data rate is set to 2.048Mb/s, the unit is forced into G.703 mode, and it transmits user data on all 32 time-lots. There is no framing information; therefore, the CRC4 MF (S2-2) switch is ignored. In all other rate settings, the unit employs G.704 framing; TS0 is reserved for signaling.

SWITCH SET 2 SUMMARY TABLE

Position

Function

Factory Default

Selected Option

 

 

 

 

 

 

S2-1

CAS MF

OFF

Disabled

 

 

 

 

 

S2-2

CRC-4 multiframe

OFF

Disabled

 

 

 

 

 

S2-3

RDL Type

OFF

V.54

S2-4

RDL Response

ON

Enabled

 

S2-5

TM from DTE

ON

Enabled

S2-6

Front Panel Switch

ON

Enabled

S2-7

NMS/VT-100 Switch

OFF

VT-100

S2-8

Line build out

ON

120 Ohms

SWITCH S2-1: CAS MULTIFRAME

CAS multiframe uses Timeslot 16 (TS16) to send multiframe (MF) alignment data. In CAS MF, a MF is defined as 16 frames, where a frame consists of 32 64kb/s timeslots, numbered 0 to 31. TS16 of the first frame in the MF contains the CAS MF alignment word in the upper four bits. The alignment word is always 0000 (binary). The 2701RC does not perform any signaling in TS16 other than to insert the MF alignment word, in order to maintain MF alignment. When CAS MF dis- abled, the unit transmits user data in TS16; therefore, up to 31 channels are available for user data. When it is enabled, TS16 is not available to the user. In this case, the user can use up to 30 channels for data. CAS MF can be used with CRC-4 MF or by itself. When enabled, both units must employ CAS MF; if one unit is set for CAS MF, and the other is not, the one using CAS MF will detect a loss of sync.

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