This section should help you figure out what speed to use when using
your modem with a communications program, or with a getty
program. Normally you just set the speed by a parameter given to
getty or by a menu in your communications program (or in a
configuration file). If for some reason that doesn't work for high
speeds, there is a workaround by giving special options to
setserial: With the spd_hi or spd_vhi options given
to setserial, setting 38400 will actually set the speed to 57600
(spd_hi) or 115200 (spd_vhi).
Make sure you have at least 16550A UARTs for higher speeds. Here are some suggested speeds:
If you use setserial test them on the command line first, and
then when you have them working, put them into
/etc/rc.d/rc.serial or /etc/rc.d/rc.local or
/etc/rc.boot/0setserial so that they are run at startup.
Make sure that you are using a valid path for setserial, and a
valid device name. You can check the settings of a serial port by
running:
setserial -a /dev/ttyS3