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Interconnect Signals
3
J7 - J10 connectors
Connectors J7 through J10 are EIA-232-D 25-pin front panel connectors,
labeled SERIAL PORT1/CONSOLE, SERIAL PORT2/TTY01, SERIAL
PORT 3, and SERIAL PORT 4. Each pin connection, signal mnemonic,
and signal characteristic for the serial port connectors is listed in the
following table.
Table 3-9. Connectors J7 - J10 interconnect signals
Pin
Number
Signal
Mnemonic
Signal Name and Description
1
Not used.
2
ETXD
TRANSMIT DATA - data to be transmitted is
furnished on this line to the modem from the terminal.
3
ERXD
RECEIVE DATA - data that is demodulated from the
receive line is presented to the terminal by the modem.
4
RTS Not
used.
5
ECTS
CLEAR TO SEND - CTS is a function supplied to the
terminal by the modem, and indicates that it is
permissible to begin transmission of a message. When
using a modem, CTS follows the off-to-on transition of
RTS after a time delay.
6
EDSR
DATA SET READY - DSR is a function supplied by
the modem to the terminal to indicate that the modem
is ready to transmit data.
7
GND
SIGNAL GROUND - Common return line connected
to the MVMExxxx ground plane. Not connected to
chassis ground.
8
EDCD
DATA CARRIER DETECT - Sent by the modem to
the terminal to indicate that a valid carrier is being
received. Not used by port 1 (J7).
9-14
Not used.
15
ERTXC4
TRANSMIT CLOCK (port 4 only) - This line can be
configured to clock output data to the modem from the
terminal.
16
Not used.
17
ERRXC4
RECEIVE CLOCK (port 4 only) - This line can be
configured to clock input data from a terminal to a
modem.
