This driver is for the HP98720 and 98721 graphics device, also known as the Renaissance. This driver has not been tested with all possible combinations of frame buffer boards and scan boards installed in the device. The driver merely checks for the existence of the device and does minimal set up.
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 Graphics Info
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
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 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.