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     dcons — dumb console device driver


     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):



     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.




     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_crom(4), ddb(4), firewire(4), fwohci(4), gdb(4), ttys(5), conscontrol(8),
     dconschat(8), fwcontrol(8)


     Hidetoshi Shimokawa <>


     This driver is currently under development.