Lucent DDM-2000 OC-3 User And Service Manual page 928

363-206-285
Issue 2, February 2000
Table B – Pin Connections for Modem Using DB-9 Cable
PC DB-9 Connector
Pin 1 - Carrier Detect
Pin 2 - Receive Data
Pin 3 - Transmit Data
Pin 4 - Data Terminal Ready
Pin 5 - Signal ground
Pin 6 - Data Set Ready
Pin 7 - Request to Send
Pin 8 - Clear to Send
Pin 9 - Ring indicator
5. Verify the telephone line is plugged into the modem.
6. STOP. YOU HAVE COMPLETED THIS PROCEDURE.
CIT
This modem detects carrier from the remote modem.
Receives data from modem
Transmits data to the modem
CIT notifies the modem that they are connected
Signal ground
Modem notifies the CIT that the modem is connected
and ready to receive data.
CIT is requesting clearance from the modem so it can
send data.
Modem notifies the CIT that it is clear to send.
Modem notifies the CIT that ring signal is present when
the modem is in an auto-answer mode.
DDM-2000 OC-3 M
Detailed Level Procedure:
ULTIPLEXER
DLP-526
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