Rockwell Automation 1440-SDM02-01RA XM-124 Standard Dynamic Measurement Module - Manuel (Page 150)

150 Rockwell Automation Publication 1440-UM001C-EN-P - May 2014
Appendix B CIP Objects
Table 72 - Get_Spectrum_Chunk/Get_Waveform_Chunk Request Parameters
Name Data Type
Description of Request Parameters
Semantics of Values
Initial DWORD Offset UINT The offset of the first 32-bit value within the
data structure to be returned. 0 <= offset < size of the data structure in DWORDs.
For example:
offset = 0 refers to bytes 0…3 (the number of lines or points
value)
offset = 1 refers to bytes 4…7 (the FMAX or period values)
offset = 2 refers to bytes 8…11 (the amplitude reference
value)
offset = 3 refers to bytes 12…15 (the first pair of normalized
values)
offset = 4 refers to bytes 16…19 (the second pair of
normalized values)
….
Number of DWORDs USINT The number of 32-bit values from the data
structure to be returned. This must be small enough to fit in the explicit message buffer.
This is likely less than the total size of the data structure so
that several calls to the service are required to get the entire
data structure.
Table 73 - Get_Spectrum_Chunk/Get_Waveform_Chunk Response Parameters
Name Data Type
Description of Response Parameters
Semantics of Values
Number of DWORDs USINT The number of 32-bit values actually returned
in the Data Chunk array of the response. (Can
be less than the number of DWORDs
requested.) If less DWORDs are returned than were requested, the end of
the data structure has been reached (the request went beyond
the end of the array).
Data Chunk Array of DWORD The requested portion of the data structure.