34 - Troubleshooting
RocketPort EXPRESS User Guide
: 2000481 Rev. G
Troubleshooting Linux Systems
Troubleshooting Linux Systems
You can use the following subsections to test the serial ports.
lcom(1)
Comtrol has available
lcom
(1), which is a multiport serial I/O test program. You
can use
lcom
in test mode to send test data to any serial port.
lcom
is available on the
Software and Documentation CD
the
latest version.
Note:
For assistance using lcom, use the manual page, lcom(1) that accompanies
the program.
File Transfer
You can transfer a file using the following information. The default settings are
9600, 8, n, 1, and no parity. To send a file you can redirect output to a device; for
example:
cat /etc/inittab > /dev/ttyRP0
Sends the contents of the
/etc/inittab
file to the
ttyRP0
device at 9600 baud, 8, n, 1,
and no parity.
Changing Serial
Port Settings (stty)
Use the following information if you need assistance changing or viewing the baud
rate settings.
To change the baud rate, use the following example, which changes the baud rate
to 19200:
stty 19200 </dev/ttyRP0
To view the current serial port settings for
ttyRP0
, enter:
stty -a </dev/ttyRP0
Note:
Settings changes via stty are only valid during current log in session. For
permanent setting changes, use the /etc/inittab file.
Setting Up
Terminals and
Modems (mgetty,
getty)
Add the appropriate line or lines to the
/etc/inittab
file then restart.
Terminal Example:
T0:23:respawn:/sbin/agetty -L ttyRP0 57600 vt100
Modem Example:
T1:23:r/sbin/mgetty -m ‘”” AT&F OK’ -D -x9 -s 115200 ttyRP0
Note:
If necessary, see the manual pages for more information on mgetty.
Testing with
minicom
You can also use
minicom
, which shipped with most Linux distributions, to test the
serial ports. A Comtrol document is available for using
