A UADP DataSetMessage header shall consist of the following fields according to this header layout:
Additional remarks:
- Field is encoded as a Variant
- The following types of DataSetMessages (Data Key Frame, Data Delta Frame, Keep Alive, etc.) are supported
The DataSetMessage header layout is shown in Figure D.4.
Figure D.4 – UADP DataSetMessage header layout
Table D.7 shows the configuration for the DataSetMessage header.
Table D.7 – UADP DataSetMessage header layout
|
Name |
Type |
Description |
|
DataSetFlags1 |
Byte |
Bit 0: Indicates whether this DataSetMessage is valid Bit range 1-2: Field Encoding 00 - VariantBit 3: DataSetMessageSequenceNumber enabled = 1 Bit 4: Status enabled = 0 Bit 5: ConfigurationVersionMajorVersion enabled = 0 Bit 6: ConfigurationVersionMinorVersion enabled = 0 Bit 7: DataSetFlags2 enabled = 1 |
|
DataSetFlags2 |
Byte |
Bit range 0-3: UADP DataSetMessage type Shall be 0000 for a Data Key Frame Shall be 0001 for a Data Delta Frame Shall be 0011 for a Keep Alive Bit 4: Timestamp enabled = 0 Bit 5: PicoSeconds enabled = 0 (not included in the DataSetMessage header) |
For a description of Data KeyFrame, Data Delta Frames and Keep Alive see OPC 10000-14.
Bibliography
ANSI/ISA-S5.1-1984 (R 1992), Instrumentation Symbols and Identification
https://webstore.ansi.org/standards/isa/isa1984r1992
__________