Grass Valley 2200 - Manual (Page 108)

5-18
Section 5 Ñ Digital Effects Interface
Send Event
This command sends an event to the other device. An event is an input, without
lasting state, which is used to trigger some action. As shown below, there are three
Send Event command data Þelds.
The event ID (ÒEIDÓ) Þeld uniquely identiÞes the event.
The pad Þeld 32-bit aligns the device Þeld.
The last Þeld contains a four-byte device identiÞer which further qualiÞes the
event to be triggered.
The only Send Event used for the switcher/DPM interface is to instruct the other
device to activate communications.
NOTE: The switcher violates this utilization of the return ID.
The switcher does not respond with Return Code messages even if the return Id in
the command sent by the DPM is nonzero.
The switcher always responds to a Send Event On-line messages with a Return
Code message even if the return ID is zero. It inserts a zero return ID into that
Return Code message and sets the data value to EID_ONLINE (= 15) instead of
SUCCESS or FAILURE.
The switcher does specify a nonzero return ID in its Send Event On-line message
and expects the DPM to echo that return ID in a Return Code message, however
the switcher ignores the data value.
Table 5-8. Send Event Command Data
Field Size Value
Event ID 2 bytes 15 = On Line
alignment pad 2 bytes any
Device 4 bytes any
Value variable any