Allen-Bradley ControlNet PLC-5, Руководство пользователя

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C-4 Data Table Crossloading
The two individual files as well as the range of files you select are
crossloaded, regardless of file type. There are some notable
exceptions; the following files are not be crossloaded even when
you select them:
- Output Image File (File 0)
- Input Image File (File 1)
- System Status File (S2)
- ControlNet Data Output File (DOF)
- ControlNet Data Input File (DIF)
- ControlNet Backup Integer File
- ControlNet Configuration File
- ControlNet I/O Status File
- ControlNet Diagnostic File
Important: If a file in the On-Demand crossload User Selectable
files is either a Timer or Counter file type, only the Accumulator
for each file element is crossloaded.
Optimizing On-Demand Crossloads
When setting up the backup system, the location of the data that needs
to be crossloaded is important. We recommend that you place all of
the crossload data into a few consecutively-addressed files. Then, by
configuring those files in the range User Selectable crossload files,
only those files will be crossloaded. This shortens the time necessary
to perform the crossload, as well as preventing unwanted files from
being crossloaded.
For example, if there are 10 integer files that need to be crossloaded,
place those 10 integer files into consecutively numbered files (e.g.
N100 through N109). Then fill the User Defined Crossload Range
Low File (Word 57 of the CHBI file) with 100 and the User Defined
Crossload Range High File (Word 58 of the CHBI file) with 109.
Now all 10 integer files will be crossloaded when User Selected File
operation of the On-Demand data table crossload is triggered.
Triggering an On-Demand Data Table Crossload
On-Demand data table crossloads are initiated by writing a value into
the On-Demand crossload command word (word 33 of the
ControlNet Backup Integer File). The On-Demand data table
crossload can be initiated from either the primary or secondary
processor.
Since the On-Demand crossload command word is located in an
integer file, you have many options concerning how the On-Demand
data table crossload gets triggered. The crossload could be triggered
via the ControlNet Backup Configuration and Status tool, via the
RSLogix5 Data Monitor, or via ladder logic in your application.