Connector pin assignments – Nortel Networks Circuit Card User Manual
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QPC841 Quad Serial Data Interface card
553-3001-211 Standard 3.00 August 2005
Connector pin assignments
Connector J1 is connected to port one, and uses the RS-232-C standard
DB-25 pinout. Connector J2 is connected to ports two, three, and four, and is
a non-standard pinout that requires an adapter cable. An adapter cable
(NT8D96) splits the J2 signals out to three standard RS-232-C connectors.
Port 2 is connected to connector A, Port 3 is connected to connector B, and
Port 4 is connected to connector C.
Table 273 shows the pinouts for connector J1, and Table 274 on
shows the pinouts for connector J2.
Table 273
Connector J1 pin assignments
Pin
number
Signal
Purpose in DTE mode
Purpose in DCE mode
1
FGD
Frame ground
Frame ground
2
TD
Received data
Transmitted data
3
RD
Transmitted data
Received data
4
RTS
Request to send (not used)
Request to send (Note 2)
5
CTS
Clear to send (Note 1)
Clear to send
6
DSR
Data set ready (Note 1)
Data set ready
7
GND
Ground
Ground
8
CD
Carrier detect (Note 1)
Carrier detect (not used)
20
DTR
Data terminal ready
Data terminal ready (Note 2)
Note 1: In DTE mode, the signals CD, DSR, and CTS are tied to +12 volts (through a resistor)
to indicate that the QSDI port is always ready to transmit and receive data.
Note 2: In DCE mode, the signals DTR, and RTS are tied to +12 volts (through a resistor) to
indicate that the QSDI port is always ready to transmit and receive data.