Nortel Networks Circuit Card Benutzerhandbuch

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 NT7D16 Data Access card
Outbound modem pooling:
Local DM user calls to the outbound modem 
access number. 
DAC answers the outbound call and drives DTR 
ON. 
Modem receives DTR and prepares to receive 
commands. 
Local DM user enters the proper commands for 
calling the remote modem. 
Remote modem answers; data call established. 
Call disconnection (DAC): 
DAC drops DTR if the local DM user drops the 
call. The modem must drop DCD. 
DAC drops DTR if the remote modem sends a 
long break or three short breaks. The modem 
must drop DCD. 
Call disconnection (modem): 
Modem drops DCD (DCD OFF for 100 ms or 
more). The DAC drops DTR and disconnects the 
local call. 
Modem drops DSR (DSR OFF for 100 ms or 
more). The DAC drops DTR and disconnects the 
local call. 
Table 158
Connect and disconnect protocol (Part 2 of 12)
Mode of 
operation
Interface application
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