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Sun Fire V880z Server and Sun XVR-4000 Graphics Accelerator Installation and User’s Guide • May 2003
When using framelock with genlock (Chapter 7), the vertical reset is always received
on the same video line. The slave cannot gain or drop a line of video with respect to
the master display device when genlocked. Use framelock and genlock together for
optimal synchronization performance.
When frame buffers are framelocked, make sure they are all running at the exact
same vertical retrace rate. This is normally achieved by selecting the same video
format (resolution and refresh rate) (see
fbconfig -help
for details). See “Enabling
Framelocking on Graphics Accelerators” on page 59.
To use the framelock features, the framelock cable is required. See “Framelock
Cable” on page 61.
To order the framelock cable, call Sun telesales at 1-800-786-0404 and request spare
part number 530-2754. You can also order the framelock cable through the Sun store
(
http://store.sun.com
) by ordering this part number under spare parts.
By default, two video streams from separate Sun XVR-4000 graphics accelerators are
not framelocked. The only exception is two streams from
doublewide
or
doublehigh
mode, on a single Sun XVR-4000 graphics accelerator; these are
inherently framelocked.
Buffer Swap Synchronization
Buffer swap synchronization enables a simultaneous swap of buffer memory
contents on all Sun XVR-4000 graphics accelerator subsystems, no matter which of
the accelerators finishes rendering its scene content last. This maintains continuity
between scenes on all displays linked together by the framelock cable. The display
can be a monitor or a large wall screen image displayed by a projector. See “Creating
a Multiscreen Application” on page 55 in this section for an outline for creating a
multiscreen application.
The software Buffer Swap Synchronization algorithm shown on page 55 is
implemented by Sun’s Xinerama support. Applications opening a window on a
Xinerama virtual frame buffer need not be concerned with this synchronization.
