Devices                                               cgeight(7D)

NAME
     cgeight - 24-bit color memory frame buffer

SYNOPSIS
     /dev/fbs/cgeightn

DESCRIPTION
     The cgeight is a 24-bit color memory  frame  buffer  with  a
     monochrome  overlay plane and an overlay enable plane imple-
     mented 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(7I).

     In addition to  the  ioctls  described  under  fbio(7I)  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 {
         int     index;         /* first element (0 origin) */
         int     count;         /* 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 Ramdac        16 bytes
              0x202000   -> P4 Register             4  bytes
     OVLBASE: 0x210000   -> Overlay Plane           1152x900x1
              0x230000   -> Overlay Enable Planea   1152x900x1
              0x250000   -> 24-bit Frame Buffera    1152x900x32

FILES
     /dev/fbs/cgeight0

     <sys/fbio.h>

SunOS 5.8           Last change: 27 Mar 1992                    1

Devices                                               cgeight(7D)

     <sys/pr_planegroups.h>

SEE ALSO
     mmap(2), fbio(7I)

SunOS 5.8           Last change: 27 Mar 1992                    2