53
MINIATURE 2-CHANNEL STATISTICAL MULTIPLEXOR
Table A-1. Main (Composite) Channel Connector.
CCITT
EIA Pin
Signal Name
Description
V.24
RS-
Circuit 232C
Number Line
108
CD 20
Data Terminal Ready
Remains positive for a period of 20
seconds then drops to a negative level
for approximately 1 second and returns
to the positive level for another 20
seconds continuously until
synchronization with the remote Mux is
established
140
21
Loop 3 Test Command Control signal from Mux to modem.
Positive level commands the attached
modem to send a remote loopback
command to the remote modem. If the
attached modem uses pin 21 as a signl
quality indication output, set pin 21 to
OFF, disabling this function (refer to
Section 4.3
)
A.2 Sub-Channel Interface
Multiplexor sub-channel interfaces are configured as asynchronous DCE RS-232
interfaces. The sub-channel connectors have RJ-45 sockets. Pin allocations are
listed in Table A-2.
