NAME

cgeight − 24-bit color memory frame buffer

SYNOPSIS

/dev/fbs/cgeight

DESCRIPTION

The cgeight is a 24-bit color memory frame buffer with a monochrome overlay plane and an overlay enable plane implemented optionally on the Sun-4/110, Sun-4/150, Sun-4/260 and Sun-4/280 system models.  It provides the standard frame buffer interface as defined in fbio(7). 

In addition to the ioctls described under fbio(7), the cgeight interface responds to two cgeight-specific colormap ioctls, FBIOPUTCMAP and FBIOGETCMAP.  FBIOPUTCMAP returns no information other than success/failure using the ioctl return value.  FBIOGETCMAP returns its information in the arrays pointed to by the red, green, and blue members of its fbcmap structure argument; fbcmap is defined in <sys/fbio.h> as:

struct fbcmap {
intindex;/∗ first element (0 origin) ∗/
intcount;/∗ number of elements ∗/
unsigned char∗red;/∗ red color map elements ∗/
unsigned char∗green;/∗ green color map elements ∗/
unsigned char∗blue;/∗ blue color map elements ∗/
};

The driver uses color board vertical-retrace interrupts to load the colormap. 

The systems have an overlay plane colormap, which is accessed by encoding the plane group into the index value with the PIX_GROUP macro (see <sys/pr_planegroups.h>). 

When using the mmap(2) system call to map in the cgeight frame buffer.  The device looks like:

DACBASE: 0x200000 -> Brooktree Ramdac16 bytes
0x202000 -> P4 Register 4 bytes
OVLBASE: 0x210000-> Overlay Plane1152x900x1
0x230000-> Overlay Enable Planea1152x900x1
0x250000-> 24-bit Frame Buffera1152x900x32

FILES

/dev/fbs/cgeight0

<sys/fbio.h>

<sys/pr_planegroups.h>

SEE ALSO

mmap(2), fbio(7)

SunOS 5.4  —  Last change: 27 Mar 1992