Grass Valley 2200 - Manual (Page 109)

5-19
Parameters
Return Code
The Return Code message returns the result of a command. All commands return
an OK or ERROR status. A return code message is sent to a control point only if the
return ID Þeld, in the message header, contains a non-zero value.
As shown below, there is one Þeld of data associated with the Return Code
message. This Þeld contains the return code itself.
Also, the return ID sent with the command is returned in the message header of
the Return Code message. This is particularly important if a control point is
sending multiple commands and needs the return ID to match a Return Code
message to its command.
NOTE: Refer to the note under Send Event above
Parameters
This appendix outlines those parameters supported for the switcher/DPM
interface. A parameter is a value that may be modiÞed and has lasting state.
Parameters are sent via the SET command. When building a Set command, the
parameter ID, its associated device, and the parameter value must be speciÞed.
In addition, a parameterÕs value may be obtained via the subscription/issue
mechanism.
Below, is a complete list of the parameters in tabular form. This list includes the
name of each parameter used in this document, the PIDÕs numeric value, its
associated devices, and the type of each parameter with its acceptable range. Bytes
and chars are 8-bit values, shorts are 16-bit values, longs are 32-bit values. Òs15.16Ó
is a signed 32-bit Þxed point value where 1.0 = 0x00010000 (0.0 = 0x00000000, -1.0
= 0xFFFF0000, 0.5 = 0x00008000, etc.). Boolean is a 16-bit value where true or on =
1 and false or off = 0. Values are in decimal unless preceded by 0x indicating
hexadecimal. The last two columns indicate who sends and receives which
commands associated with each PID.ÒTxÓ means the device transmits the
message; ÒRxÓ means that device receives the message. ÒSUBÓ indicates subscribe
append or replace messages. ÒSUB-IÓ indicates subscribe immediate messages.
Table 5-9. Return Code Message Data
Field Size Value
Return code value 4 bytes 0 = OK / Success
0xFFFFFFFF = Error / Failure