Albalá Ingenieros AVP1221C01, Руководство пользователя

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Albalá Ingenieros | Manual AVP1221C01
4.2. Functional description
Selection of the active input to the preselector is done remotely, either by a PC or with a
control keypad. The following section will explain the various ways to connect the
preselector to PC or control keypad.
The AVP1221C01 has two different switching modes, depending upon how it will be
used.
When only one preselector module is being used then the AVP1221C01 operates in
Master Mode. In Master Mode the AVP1221C01 only responds to commands received
from the internal communications bus of the mounting frame directed to the slot where
the preselector is installed.
In systems that use multiple preselectors that must all switch at the same time, for
example when switching component video, the module can be operated in Slave Mode,
in which it responds to commands sent to a module in Master Mode installed in a
different slot. In Slave Mode the module continues to respond to commands sent to the
slot where it is installed.
The switching action between the different inputs can be performed with four different
switching times, depending upon the configuration of the preselector and the presence
or absence of a vertical sync signal.
- When the switching time is set to FAST the preselector will switch as soon as it
receives a command to do so. Switching also takes place immediately, even when
commanded to do so at a different time if no vertical sync signal is present.
- When the switching time is set to FIELD and a signal is present at Input 1 the
preselector will switch during the first vertical interval produced after receiving the
switching command.
- When the switching time is set to FRAME and a signal is present at Input 1 the
preselector will switch during the first vertical interval between Field Two and Field
One produced after receiving the switching command.
- Finally, if the switching time is set to SLAVE then the preselector will switch at the
same instant that the module installed directly to the right switches.
The following section will explain the two most common configurations of the
AVP1221C01 for switching during the vertical interval for both composite video and
component video.
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