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Configuring FreeBSD to use a VESA Console

Some users of FreeBSD need their console to support a higher resolution than the usual 25 line console display. Certain console applications might need this higher resolution to display information, making it easier to read. For this purpose, FreeBSD uses a utility alled vidcontrol. This, along with VESA options allow for resolutions as high as 1024x768 in the console.

Configuring the kernel

The FreeBSD kernel config file simply needs two lines to be added so that the default console will display higher resolutions.

options         VESA
options         SC_PIXEL_MODE

These options compile the VESA module into the kernel and turn on the Syscons pixel support. For more information about these options, frefer to the manual pages for vidcontrol and syscons.

After adding these lines, of course you must recompile your kernel and install it. For more information on compiling a custom kernel, refer to the FreeBSD Handbook : Kernel Section

Enabling console resolutions at boot time

The next step after compiling the new kernel is to reboot the system, and then check what modes are available for the console. For this, we use the vidcontrol tool to find this information.

vidcontrol -i mode

Hopefully, a decent mode such as 135x25 or 100x37 is displayed and available. If so, try the following command:

vidcontrol 132x25

or:

vidcontrol 100x37

If your display refreshes to the newer high resolution, then you are set. If the screen goes blank, then this resolution is not supported by the VESA module call to your video card. You might have to switch to another console and try a setting that works. Once you have found this setting, simply add the appropriate lines to /etc/rc.conf so that your console uses this resolution at boot:

allscreens_flags="-g 135x25 VESA_1024x768'

or:

allscreens_flags="-g 100x37 VESA_800x600"