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Diffstat (limited to 'Documentation/serial-console.txt')
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diff --git a/Documentation/serial-console.txt b/Documentation/serial-console.txt deleted file mode 100644 index 9a7bc8b3f479..000000000000 --- a/Documentation/serial-console.txt +++ /dev/null @@ -1,109 +0,0 @@ - Linux Serial Console - -To use a serial port as console you need to compile the support into your -kernel - by default it is not compiled in. For PC style serial ports -it's the config option next to "Standard/generic (dumb) serial support". -You must compile serial support into the kernel and not as a module. - -It is possible to specify multiple devices for console output. You can -define a new kernel command line option to select which device(s) to -use for console output. - -The format of this option is: - - console=device,options - - device: tty0 for the foreground virtual console - ttyX for any other virtual console - ttySx for a serial port - lp0 for the first parallel port - ttyUSB0 for the first USB serial device - - options: depend on the driver. For the serial port this - defines the baudrate/parity/bits/flow control of - the port, in the format BBBBPNF, where BBBB is the - speed, P is parity (n/o/e), N is number of bits, - and F is flow control ('r' for RTS). Default is - 9600n8. The maximum baudrate is 115200. - -You can specify multiple console= options on the kernel command line. -Output will appear on all of them. The last device will be used when -you open /dev/console. So, for example: - - console=ttyS1,9600 console=tty0 - -defines that opening /dev/console will get you the current foreground -virtual console, and kernel messages will appear on both the VGA -console and the 2nd serial port (ttyS1 or COM2) at 9600 baud. - -Note that you can only define one console per device type (serial, video). - -If no console device is specified, the first device found capable of -acting as a system console will be used. At this time, the system -first looks for a VGA card and then for a serial port. So if you don't -have a VGA card in your system the first serial port will automatically -become the console. - -You will need to create a new device to use /dev/console. The official -/dev/console is now character device 5,1. - -(You can also use a network device as a console. See -Documentation/networking/netconsole.txt for information on that.) - -Here's an example that will use /dev/ttyS1 (COM2) as the console. -Replace the sample values as needed. - -1. Create /dev/console (real console) and /dev/tty0 (master virtual - console): - - cd /dev - rm -f console tty0 - mknod -m 622 console c 5 1 - mknod -m 622 tty0 c 4 0 - -2. LILO can also take input from a serial device. This is a very - useful option. To tell LILO to use the serial port: - In lilo.conf (global section): - - serial = 1,9600n8 (ttyS1, 9600 bd, no parity, 8 bits) - -3. Adjust to kernel flags for the new kernel, - again in lilo.conf (kernel section) - - append = "console=ttyS1,9600" - -4. Make sure a getty runs on the serial port so that you can login to - it once the system is done booting. This is done by adding a line - like this to /etc/inittab (exact syntax depends on your getty): - - S1:23:respawn:/sbin/getty -L ttyS1 9600 vt100 - -5. Init and /etc/ioctl.save - - Sysvinit remembers its stty settings in a file in /etc, called - `/etc/ioctl.save'. REMOVE THIS FILE before using the serial - console for the first time, because otherwise init will probably - set the baudrate to 38400 (baudrate of the virtual console). - -6. /dev/console and X - Programs that want to do something with the virtual console usually - open /dev/console. If you have created the new /dev/console device, - and your console is NOT the virtual console some programs will fail. - Those are programs that want to access the VT interface, and use - /dev/console instead of /dev/tty0. Some of those programs are: - - Xfree86, svgalib, gpm, SVGATextMode - - It should be fixed in modern versions of these programs though. - - Note that if you boot without a console= option (or with - console=/dev/tty0), /dev/console is the same as /dev/tty0. In that - case everything will still work. - -7. Thanks - - Thanks to Geert Uytterhoeven <geert@linux-m68k.org> - for porting the patches from 2.1.4x to 2.1.6x for taking care of - the integration of these patches into m68k, ppc and alpha. - -Miquel van Smoorenburg <miquels@cistron.nl>, 11-Jun-2000 |