DCONS(4)               FreeBSD Kernel Interfaces Manual               DCONS(4)

NAME
     dcons - dumb console device driver

SYNOPSIS
     To compile this driver into the kernel, place the following lines in your
     kernel configuration file:

           options GDB
           device firewire
           device dcons

     Alternatively, to load the driver as a module at boot time, place the
     following line in your kernel configuration file:

           options GDB

     and in loader.conf(5):

           dcons_load="YES"

DESCRIPTION
     The dcons device is a simple console device which just reads from and
     writes to an allocated buffer for input and output respectively.  It is
     of no use by itself and it is supposed that the buffer is accessed via a
     bus like firewire(4) or kvm(3) for interaction.

     The buffer consists of 4 channels.  There are 2 ports, one for the
     console TTY and another is GDB port, then each port has an input channel
     and an output channel.

FILES
     /dev/dcons
     /etc/ttys

EXAMPLES
     If you want to run getty(8) on dcons, insert the following line into
     ttys(5) and send a HUP signal to init(8) using kill(1).

           dcons   "/usr/libexec/getty std.9600"   vt100   on  secure

     Once the fwohci(4) device is initialized to allow physical access, the
     buffer can be accessed from another host via a firewire(4) bus using the
     dconschat(8) application.  See dconschat(8) for more details.

     If you want to use dcons as a gdb(1) port, add the following line into
     loader.conf(5):

           dcons_gdb="1"

SEE ALSO
     dcons_crom(4), ddb(4), firewire(4), fwohci(4), gdb(4), ttys(5),
     conscontrol(8), dconschat(8), fwcontrol(8)

AUTHORS
     Hidetoshi Shimokawa <simokawa@FreeBSD.org>

BUGS
     This driver is currently under development.

FreeBSD 13.1-RELEASE-p6        January 26, 2008        FreeBSD 13.1-RELEASE-p6