Get_spectrum_chunk/get_waveform_chunk – Rockwell Automation 1440-VSE02-01RA XM-122 gSE Vibration Module User Manual
Page 176

Publication GMSI10-UM013D-EN-P - May 2010
166 DeviceNet Objects
1
Attributes can only be set while the device is in Program Mode. See the description of the Device Mode Object
for more information.
Get_Stored_Spectrum_Chunk/Get_Stored_Waveform_Chunk
These services function just like Get_Spectrum_Chunk and
Get_Waveform_Chunk (described below) except they operate on the stored
spectrum or waveform data rather than the current spectrum or waveform
data. A spectrum or waveform data set is stored in conjunction with the
triggered trend’s trigger event if the triggered trend is enabled. The Storage
Option attribute determines whether the spectrum or waveform data is
stored.
Get_Spectrum_Chunk/Get_Waveform_Chunk
These services return a portion of the respective data structure. It is likely that
the spectrum and waveform data structures will be too large to transfer over
the network in one message. These services allow the data structures to be
transferred over the network in smaller portions so that the explicit message
buffer does not need to be so large.
The Spectrum Data structure contains an array of values that, taken together,
are the output of the spectrum measurement performed by the
Spectrum/Waveform Measurement Object on the input signal. The size of the
Spectrum Data structure and format of the data array depends on the Data
4C
h
Instance
Get_Waveform_Chunk
Upload a portion of the
current Waveform data.
4D
h
Instance
Get_Stored_Spectrum_
Chunk
Upload a portion of the
stored Spectrum data.
4E
h
Instance
Get_Stored_Waveform_
Chunk
Upload a portion of the
stored Waveform data.
Table C.53 Spectrum Waveform Measurement Object Services
Service
Code
Class/Instance Usage
Name
Description
IMPORTANT
The gSE spectrum is not stored (these services will return a
"resource unavailable" error for instances 3 and 4).