On Mon, 1 Sep 2003, Randy Kramer wrote: > On Monday 01 September 2003 10:50 am, Bonny wrote: > > What is the meaning of the "syncongreen" option which can be inserted > > into a "Monitor Section"? > > My first smart-ass answer is that if you need to ask, you don't need to know. > ;-) > > What I think I know: > > Some monitors have 3 or 4 BNC connectors instead of the 15 pin DIN connector > typical of modern (S)VGA monitors. When there are 4 BNC connectors, the sync > signal must be sent on one of those by itself. If there are only 3, the sync > signal must be combined with one of the color signals, usually green (I > think). > > What I don't know: > > In the typical 15 pin DIN connection, I don't know if sync is a separate pin > or not. VGA connectors have separate horizontal and vertical syncs. The BNC versions of those have 5 connectors. If you have 4 BNC connectors that is "composite sync" with the horizontal and vertical syncs sharing the same sync line. If you have 3 BNC connectors the composite sync is added to the green analog line. While some video cards can produce composite syncs or sync-on-green, not all, perhaps even most, cannot. There are, however, converters that go between the monitor and video card that can change VGA into sync-on-green or composite. The schematics are simple. Mark. _______________________________________________ XFree86 mailing list XFree86@xxxxxxxxxxx http://XFree86.Org/mailman/listinfo/xfree86
