GRF(4)                OpenBSD Programmer's Manual (HP300)               GRF(4)

NAME
     grf - HP graphics frame buffer device interface

SYNOPSIS
     grf* at dvbox?
     grf* at gbox?
     grf* at hyper?
     grf* at rbox?
     grf* at topcat?

     ite* at grf?

DESCRIPTION
     This is a generic description of the frame buffer device interface.

     The devices to which this applies are the 98544, 98545 and 98547 Topcat
     graphics cards (also known as HP300H devices), the 98548, 98549 and 98550
     Catseye graphics cards, the A1416A Kathmandu graphics cards, the 98700
     Gatorbox graphics box, the 98720 Renaissance graphics box, the 98730
     DaVinci graphics box, and the A1096A Hyperion graphics cards.

     The basic programming of the grf? devices involves opening the device
     file, mapping the control registers and frame buffer addresses into user
     space, and then manipulating the device as the application requires.  The
     address mapping is controlled by an ioctl(2) call to map the device into
     user space, and an unmap call when finished.

     The ioctls supported by OpenBSD are:

     GRFIOCGINFO  Get Graphics Info

                  Get info about device, setting the entries in the grfinfo
                  structure, as defined in <machine/grfioctl.h>:

                  struct  grfinfo {
                          int     gd_id;          /* HP-UX identifier */
                          caddr_t gd_regaddr;     /* control registers physaddr */
                          int     gd_regsize;     /* control registers size */
                          caddr_t gd_fbaddr;      /* frame buffer physaddr */
                          int     gd_fbsize;      /* frame buffer size */
                          short   gd_colors;      /* number of colors */
                          short   gd_planes;      /* number of planes */
                  /* new stuff */
                          int     gd_fbwidth;     /* frame buffer width */
                          int     gd_fbheight;    /* frame buffer height */
                          int     gd_dwidth;      /* displayed part width */
                          int     gd_dheight;     /* displayed part height */
                          int     gd_pad[6];      /* for future expansion */
                  };

     GRFIOCON     Graphics On

                  Turn graphics on by enabling CRT output.  The screen will
                  come on, displaying whatever is in the frame buffer, using
                  whatever colormap is in place.

     GRFIOCOFF    Graphics Off

                  Turn graphics off by disabling output to the CRT.  The frame
                  buffer contents are not affected.

     GRFIOCMAP    Map Device to user space

                  Map in control registers and frame buffer space.  Once the
                  device file is mapped, the frame buffer memory and registers
                  are accessible.

     GRFIOCUNMAP  Unmap Device

                  Unmap control registers and frame buffer space.

FILES
     /dev/grf?  OpenBSD interface special files

EXAMPLES
     This short code fragment is an example of opening some graphics device
     and mapping in the control and frame buffer space:

     #define GRF_DEV <some_graphics_device>  /* /dev/grfN */

     struct fbstruct *regs;  /*  fbstruct = gboxfb, rboxfb, etc. */
     u_char *Addr, frame_buffer;
     struct grfinfo gi;
     int disp_fd;

     disp_fd = open(GRF_DEV, O_WRONLY);
     if (ioctl(disp_fd, GRFIOCGINFO, &gi) < 0) return -1;
     ioctl(disp_fd, GRFIOCON, 0);

     if (ioctl(disp_fd, GRFIOCMAP, &Addr) < 0) {
             ioctl(disp_fd, GRFIOCOFF, 0);
             return -1;
     }
     regs = (fbstruct *)Addr;               /* Control Registers   */
     frame_buffer = (u_char *)Addr + gi.gd_regsize; /* Frame buffer mem */

DIAGNOSTICS
     None under OpenBSD.

     HP-UX The CE.utilities/Crtadjust programs, running in HP-UX compatibility
     mode, can be used for each specific device.

SEE ALSO
     ioctl(2), cons(4), dvbox(4), gbox(4), hil(4), hyper(4), intro(4), ite(4),
     rbox(4), topcat(4)

OpenBSD 3.5                      June 9, 1993                                2
