Comtrol DM ATS-LNX - Manual (Page 22)

AUX A Port 22
AUX A Port
This section discusses the following topics:
• How to change the default function of the AUX A port from the default
configuration to a standard RS-232 serial port.
• The default modem initialization string.
By default, AUX A (ttyS1) is configured for use with a modem.
Using the AUX A Port as a Standard tty Port
To disable the dial-in support on the AUX port, use a # character to comment out
the ttyS1 line in the /etc/inittab file.
#T1:23:respawn:+/sbin/mgetty -x0 -s 115200 ttyS1
In both cases you will have to either reboot or do one of the following:
• Notify init of the changes with this command:
# telinit q
• Kill any getty or mgetty running on the port in question:
# ps
PID TTY STAT TIME COMMAND
1 ? S 0:05 init [2]
2 ? SW 0:00 [keventd]
[...]
1149 ttyS0 S 0:00 /sbin/getty -L ttyS0 57600 vt100
[...]
# kill 1149
Modem Initialization
The ATS-LNX mgetty configuration uses the AT&F1 command to set the externally
attached modem to factory defaults.
Note: If factory default initialization string is not working, consult your modem's
manual for the proper initialization string.
The initialization string should set the modem to:
• Locked DTE baud rate.
• Hardware flow control (RTS/CTS).
• Verbose result codes.
• Reset when DTR dropped.
The modem initialization string is contained in the /etc/inittab file:
T1:23:respawn:+/sbin/mgetty -m '"" AT&F1 OK' -D -x0 -s 115200 ttyS1
Note: Other modem types may work with the AT&F modem initialization
command.