| Applies to:
PcVue all versions. |
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| Summary:
In article KB243 there is a description of the quality values you can find in HDS tables. However, the quality value 64 is very specifc and requires a separate explanation. |
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| Details:
The quality value 64 (or Hexadecimal OPC code 0x40 = Uncertain) mainly appears when the HDS was not shut down correctly (crash or kill task). The HDS uses a file (Watchdog.dat) in the HDS folder of the project. When the HDS shuts down correctly this file is deleted. If, at PcVue startup, this file already exists then the HDS records a quality of 64 for all trend points. The timestamp of these points corresponds to the last modification time of the file. |
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Created on: 29 Aug 2012 Last update: 13 May 2024