Matrox Meteor-II, Installation And Hardware Reference Manual

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Matrox Meteor-II /Multi-Channel grab section 33
Synchronization
Matrox Meteor-II /Multi-Channel can operate in either slave or master mode.
Slave mode
• In slave mode, the video source provides the synchronization information to
Matrox Meteor-II /Multi-Channel. It can accept one of the following
synchronization schemes:
- The video source encodes the synchronization signals on the analog video signal
provided to the board.
- The video source supplies the horizontal and/or vertical synchronization signals
separately in TTL format.
- The video source provides a composite synchronization signal in TTL format,
separate from the analog video.
• Synchronization information can be sent either with the video data, or on a
separate analog synchronization channel.
Master mode
• In master mode, Matrox Meteor-II /Multi-Channel generates (using the PSG)
the horizontal and/or vertical (TTL) synchronization signals and supplies them
to the video source. This allows the video source to synchronize to the board.
Trigger
Matrox Meteor-II /Multi-Channel accepts an external trigger input which allows
image acquisition to be synchronized to external events. The board can operate
in one of two modes, and the selected mode is specified by the DCF.
Matrox Meteor-II /Multi-Channel can operate in next valid frame/field mode
When in this mode, the digitizer waits for the next valid frame or field (as specified
by the DCF file) before commencing the grab. This trigger mode functions in one
of three ways:
• Edge-triggered monoshot acquisition: The VIA (Video Interface Asic) waits for
the rising/falling edge to capture a single frame.
• Edge-triggered continuous acquisition: The VIA waits for the rising/falling edge
to start a continous grab.
• Level-sensitive "continuous" acquisition: The VIA grabs continuously while the
level of the trigger is high/low.