GENLOCK(7)GENLOCK(7)NAMEgenlock - genlock capability on IRIS-4D Series machines
DESCRIPTION
Genlock is the synchronizing of two video outputs, such that the
horizontal and vertical sync signals are aligned. For genlock to be
possible, the two video outputs must be running the same video format.
All IRIS-4D Series graphics systems have some genlock capability.
A graphics pipe normally has on it a clock source, such as a crystal,
that is used to generate internal timings. To genlock a graphics pipe,
you must supply a suitable external clock; you must then inform the
software that it is to use the supplied clock instead of its internal
default.
Genlock is controlled by the setmon(1G) command and the setmonitor(3G)
IrisGL function call. To enable or disable genlock, you must use one of
these. For a full description of the various parameters available please
consult those man pages.
When genlocking two IRIS-4D Series machines together, you should
designate one system as the `master' and the other as the `slave'. The
master system will run normally and use its internal crystal to generate
its sync signal. The slave system will take the sync signal from the
first system and use it; the call to setmon(1G) or setmonitor(3G) should
only be done on the slave system. To route the sync signal would
typically require a coaxial cable from the `Sync Output' jack of the
master system to the `Genlock Input' jack of the slave system. Also, this
signal should usually be terminated at the destination end with a 75-ohm
resistor.
If more than two graphics systems are to be locked together, you must
still designate one system as the `master'; all other systems are
`slaves'. Care must be taken in this setup to correctly route the sync
from the master to all of the slaves; this should normally be done in
daisy-chain fashion. Note that this connection must be terminated only
once, at the last slave in the chain.
NOTE
In some multi-screen stereo applications it is desirable to genlock
stereo screens together. Care must be taken to ensure that right-eye
views are locked together. For some older stereo formats, this may
require several attemps; the system may lock the left eye of one screen
to the right eye of the other. If this occurs, turn genlock off and try
the genlock again.
Removing and reconnecting the sync signal from the sync input is not
suggested, as this may cause problems with the hardware. Genlock should
always be turned off via setmon(1G) or setmonitor(3G) before connecting
or disconnecting the sync signal.
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GENLOCK(7)GENLOCK(7)
In a IRIS-4D system with multiple graphics pipelines, these pipelines are
not automatically genlocked; they run completely independantly, exactly
as if they were in different systems. If it is desired to run the
graphics pipes genlocked together, this must be done by the user as
described above.
In general, the input sync reference signal must be identical to the
output sync signal for that format; in other words, you can generally
only lock together identical video formats.
SEE ALSOsetmon(1G), setmonitor(3G)
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