11.10.2 Limitations Of The Codesys Visualization - WAGO -I/O-IPC-C6 Manual

130 CoDeSys 2.3 Runtime Environment

11.10.2 Limitations of the CoDeSys Visualization

The visualization integrated in CoDeSys has the three variants "HMI",
"TargetVisu" and "WebVisu", which are all supported by the I/O-IPC. Depending
on the process variant, there are technological limitations.
Several options of the complex visualization objects "Alarm" and "Trend" are
only provided by the "HMI" version. This applies for example to the sending of
emails as a response to an alarm or to the navigation through historical trend data
as well as the creation of the data.
In comparison to "HMI", Web visualization on the I/O-IPC is carried out within
significantly narrower physical limits. While "HMI" can access almost unlimited
resources on a desktop PC, the following limitations must be observed when using
Web visualization:
Adaptation to the File System
The overall size of the PLC program, visualization files, bitmaps, log files,
configuration files etc. must fit into the file system.
Process Data Memory
Web visualization uses its own protocol for the exchange of process data between
applet and control. In doing so, process data is transmitted ASCII coded. The
pipe-symbol ("|") is used between two process values as a separating character.
Therefore, the space requirement for a process data variable in the process data
memory is dependent not only on the data type, but also on the process value
itself. Thus, a variable of the "WORD" type occupies between one byte for the
values 0 through 9 and five bytes for values from 10000.
The selected format (ASCII + |) only permits a rough estimate of the space
requirement for the individual process data in the process data buffer. If the size
of the ASCII coded process data is exceeded, Web visualization no longer works
according to expectations.
WAGO-I/O-SYSTEM 750
758-874/000-131 WAGO-I/O-IPC-C6
Manual
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