8
SW1-6 and SW1-7 Clock Modes
Use Switches SW1-6 and SW1-7 to configure the 2707 for internal,
external, or receive recover clock mode.
SW1-8: Enable/Disable Loop Tests from DTE
Use Switch SW1-8 to allow Model 2707 to enter loopback tests when the
DTE raises the appropriate loop request pin.
Table 3:
SW1-6 and SW1-7 Clock Modes
SW1-6
SW1-7
Clock Mode
ON
ON
Network (Received Recovered)
ON
OFF
Internal
OFF
ON
External
OFF
OFF
Network (Received 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 timing.
SW1-8
Setting
Off
Response to DTE Loopback Request Enabled
On
Response to DTE Loopback Request Disabled
