September 10, 2001 RBOX 4 hp300

### NAME

rbox - HP98720 ``Renaissance'' graphics device interface

### SYNOPSIS

rbox* at intio? rbox* at dio? scode ?

### DESCRIPTION

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`.

### FILES

```/dev/grf?`
  BSD special file
```/dev/crt98720`
```/dev/ocrt98720`
  HP-UX starbase special files
```/dev/MAKEDEV.hpux`
  script for creating HP-UX special files

### EXAMPLES

This is a short segment of code showing how the device is opened and mapped into user process address space assuming that it is grf0: `

    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 */

`

### DIAGNOSTICS

None under BSD. The HP-UX CE.utilities must be used.

### ERRORS

[```ENODEV`]
  no such device.

[```EBUSY`]
  Another process has the device open.

[```EINVAL`]
  Invalid ioctl specification.

### SEE ALSO

ioctl(2), grf(4), ite(4)

For extensive code examples using the Renaissance, see the X device dependent source.

### BUGS

Not tested for all configurations of scan board and frame buffer memory boards.