19
CHAPTER 3: Installation
Table 3-1. Jumper Selection.
Jumper
Factory
Possible
Identity
Setting
Position Function
Interface
V.35
V.35
The interface is CCITT V.35.
Board
V.11
The interface is EIA RS-449/RS-422,
CCITT V.36/V.11, CCITT X.21/V.11, or
EIA RS-530.
GND
Connect Connect: Protective ground connected to
signal ground.
Disconn
Disconn
Disconn: Protective ground disconnected
from signal ground.
TC G.703 LBT
LBT
The Tx-pair timing is the recovered clock
from the CCITT G.703 Rx pair.
EXT
The Tx-pair and transmit timing are from
the RS-422/V.35 external source.
INT
The Tx-pair and transmit timing are from
the internal source.
LBT
DTE
DTE
Connection to DTE, with transmit and
receive timing derived from the unit’s
recovered clock.
DCE
Connection to DCE, while both the DCE
and the unit operate with external
transmit timing.
DCE 21
Connection to X.21 DCE. The unit’s
transmit and receive timing are derived
from the DCE.
Bit rate
64
64
Data rate is 64 kbps.
56
Data rate is 56 kbps.
48
Data rate is 48 kbps.
Mark
“1”
MARK on V.35 or V.11 interface equals
“1” on G.703 interface.
“0”
“0”
MARK on V.35 or V.11 interface equals
“0” on G.703 interface.