setserial Version 2.10 Setserial is a program which allows you to look at and change various attributes of a serial device, including its port, its IRQ, and other serial port options. Starting with Linux 0.99 pl10, only the COM1-4 ports are configured, using the default IRQ of 4 and 3. So, if you have any other serial ports provided by other boards (such as an AST Fourport), or if COM3-4 have been a non-standard IRQ so that you can use time simultaneously with COM1-2, you *must* use this program in order to configure those serial ports. The simplest way to configure the serial ports is to copy the provided rc.serial file to /etc/rc.serial, and then add to /etc/rc the lines: if [ -f /etc/rc.serial ]; then sh /etc/rc.serial fi Take a look at /etc/rc.serial; it was written to be relatively easy to modify, and you may need to modify it so that it works best in your environment. ------------------------------------------------------- Here is setserial's command line syntax: usage: ./setserial [-abgqvVW] serial-device [cmd1 [arg]] [cmd2] ... Available options: -a Display all possible information about the port -b Display boot-time level of information -q Quiet flag -v Verbose flag -g Get and display the serial information of all serial ports on the machine -V Display the current Version and then exit -W Do wild interrupt initialization and then exit Available commands: (* = Takes an argument) (^ = can be preceded by a '^' to turn off the option) * port set the I/O port * irq set the interrupt * uart set UART type (none, 8250, 16450, 16550, 16550A * baud_base set base baud rate (CLOCK_FREQ / 16) * divisor set the custom divisor (see spd_custom) ^ fourport configure the port as an AST Fourport autoconfigure automatically configure the serial port ^ auto_irq try to determine irq during autoconfiguration ^ skip_test skip UART test during autoconfiguration ^ sak set the break key as the Secure Attention Key ^ session_lockout Lock out callout port across different sessions ^ pgrp_lockout Lock out callout port across different process groups ^ split_termios Use separate termios for callout and dailin lines ^ hup_notify Notify a process blocked on opening a dialin line when a process has finished using a callout line by returning EAGAIN to the open. ^ callout_nohup Don't hangup the tty if carrier detect drops on a callout line. spd_hi use 56kb instead of 38.4kb spd_vhi use 115kb instead of 38.4kb spd_cust use the custom divisor to set the speed at 38.4kb (baud rate = baud_base / custom_divisor) spd_normal use 38.4kb when a buad rate of 38.4kb is selected Use a leading '0x' for hex numbers. CAUTION: Using an invalid port can lock up your machine!