Rockwell Automation 1440-SDM02-01RA XM-124 Standard Dynamic Measurement Module - Manuel (Page 149)

Rockwell Automation Publication 1440-UM001C-EN-P - May 2014 149
CIP Objects Appendix B
Object on the input signal. The Waveform Data array values are normalized and
must be converted to floating point to obtain the true values.
The total size of the Waveform Data structure in DWORDs is 3 + (Number of
Waveform Points
/ 2).
The Waveform Data is an array of INT (16-bit signed integers ranging from -
32768 to 32767). The number of INTs in the Waveform Data array is equal to
the Number of Waveform Points. To convert the normalized Waveform Data
into floating point values, use the following equations:
Where Float Data
n
is the value for the nth waveform point, and 0 n Number
of Waveform Points .
The Get_Spectrum_Chunk and Get_Waveform_Chunk services use the same
request and response parameters.
Table 71 - Waveform Data Structure
Byte (DWORD) offset
within structure
Structure Member Data Type Description
0 (0) Number of Waveform
Points UDINT Number of points in the waveform data. This must be equal to the Number
of Waveform Points attribute setting. It is provided within this structure
to assist in determining the size of the structure.
4 (1) Period REAL The period of the waveform.
This is the actual period of the waveform and may vary from the Period
attribute setting.
8 (2) Amplitude Reference REAL Normalization factor
This factor is used to convert the normalized array data into floating point
values.
12 (3) Normalized Value Array Array of INT The normalized waveform data points
These must be converted to floating point values using the Amplitude
Reference value.
Float Data
n
Amplitude Reference
Normalized Data
n
32768
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