The Renaissance can be configured at either the ``internal'' address (frame buffer address 0x200000, control register space address 0x560000) or at an external select code less than 32. At the internal address it will be the ``preferred'' console device. The hardware installation manual describes the procedure for setting these values.
A user process communicates to the device initially by means of ioctl(2) calls. For the HP-UX ioctl(2) calls supported, refer to HP-UX manuals. The BSD calls supported are:
GRFIOCGINFO
Get info about device, setting the entries in the
grfinfo
structure, as defined in
<hpdev/grfioctl.h
>.
For the standard 98720, the number of planes should be 4. The number of
colors would therefore be 15, excluding black. If one 98722A frame buffer
board is installed, there will still be 4 planes, with the 4 planes on the
colormap board becoming overlay planes. With each additional 98722 frame
buffer board 4 planes will be added up to a maximum of 32 planes total.
GRFIOCON
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
Turn graphics off by disabling output to the CRT. The frame buffer contents are not affected.
GRFIOCMAP
Map in control registers and framebuffer space. Once the device file is
mapped, the frame buffer structure is accessible. The structure describing
the 98720 is defined in
hpdev/grf_rbreg.h
.
/dev/grf?
/dev/crt98720
/dev/ocrt98720
/dev/MAKEDEV.hpux
struct rboxfb *rbox;
u_char *Addr, frame_buffer;
struct grfinfo gi;
int disp_fd;
disp_fd = open("/dev/grf0",1);
if (ioctl (disp_fd, GRFIOCGINFO, &gi) < 0) return -1;
(void) ioctl (disp_fd, GRFIOCON, 0);
Addr = (u_char *) 0;
if (ioctl (disp_fd, GRFIOCMAP, &Addr) < 0) {
(void) ioctl (disp_fd, GRFIOCOFF, 0);
return -1;
}
rbox = (rboxfb *) Addr; /* Control Registers */
frame_buffer = (u_char *) Addr + gi.gd_regsize; /* Frame buffer memory */
ENODEV
]
EBUSY
]
EINVAL
]For extensive code examples using the Renaissance, see the X device dependent source.