SMG(4) OpenBSD Programmer's Manual (VAX) SMG(4)NAMEsmg - Small Monochrome Graphics frame buffer
SYNOPSIS
smg0 at vsbus0 csr 0x200f0000
wsdisplay* at smg?
DESCRIPTION
The smg is a monochrome frame buffer found on-board most VAXstation 3100
systems.
The smg driver interfaces the frame buffer with the wscons(4) console
framework. It does not provide direct device driver entry points but
makes its functions available via the internal wsdisplay(4) interface.
When a color option board (either a gpx(4) or a spx frame buffer) is
installed, the smg driver will not attach by default, since the color
option takes over the video connector on the back of the system.
However, the output signal pins are independent, and it is possible to
connect a monochrome video cable even if a color option board is
installed. To force the smg driver to attach in this case, change the
device flags to 1. It will however not be possible to use the monochrome
frame buffer as the OpenBSD console in this case.
SEE ALSOintro(4), vsbus(4), wscons(4), wsdisplay(4)OpenBSD 4.9 March 31, 2008 OpenBSD 4.9