Technical data

tcx(7D) Devices SunOS 5.5
NAME tcx − 24-bit SBus color memory frame buffer
SYNOPSIS /dev/fbs/tcx
DESCRIPTION tcx is a 8/24-bit color frame buffer and graphics accelerator, with 8-bit colormap, and
overlay/enable planes. It provides the standard frame buffer interface defined in
fbio(7I).
tcx has two control planes which define how the underlying pixel is displayed. The
display modes are 8-bit (8 bits taken from low-order 8 bits of pixel) through a colormap;
24-bit through a gamma-correction table; 24-bit through the colormap; or 24-bit direct.
The colormap is shared by both 24-bit and 8-bit modes.
The tcx has registers and memory that may be mapped with mmap(2), using the offsets
defined in <sys/tcxreg.h>.
There is an 8-bit only version of tcx which operates the same as the 24-bit version, except
that the 24-bit-related mappings can not be made.
tcx accepts the following ioctls, defined in <sys/fbio.h> and <sys/visual_io.h>, and
implemented as described in fbio(7I).
FBIOGATTR FBIOGCURSOR
FBIOGTYPE FBIOSCURPOS
FBIOPUTCMAP FBIOGCURPOS
FBIOGETCMAP FBIOGCURMAX
FBIOSATTR FBIOGXINFO
FBIOSVIDEO FBIOMONINFO
FBIOGVIDEO FBIOVRTOFFSET
FBIOVERTICAL VIS_GETIDENTIFIER
FBIOSCURSOR
The value returned by VIS_GETIDENTIFIER is "SUNW,tcx".
Emulation mode (FBIOGATTR, FBIOSATTR) may be either none, FBTYPE_SUN3COLOR,
or FBTYPE_MEMCOLOR.
FBIOPUTCMAP returns immediately, although the actual colormap update may be
delayed until the next vertical retrace. If vertical retrace is currently in progress, the new
colormap takes effect immediately.
FBIOGETCMAP returns immediately with the currently-loaded colormap, unless a color-
map write is pending (see above), in which case it waits until the colormap is updated
before returning. This may be used to synchronize software with colormap updates.
The size and linebytesvalues returned by FBIOGATTR, FBIOGTYPE and FBIOGXINFO are
the sizes of the 8-bit framebuffer. The proper way to compute the size of a framebuffer
mapping is
size=linebytes∗height∗bytes_per_pixel
7D-344 modified 10 Nov 1993