Rules For Packaging Digital Information - WAGO 750-370 Manual

82 Function Description
Submodule types that allocate no data
If data volumes larger than actually required to represent the physical channels are
always used for digital I/O modules, data processing is very inefficient as data
without any actual information also has to be transmitted.
For subsequent use of additional allocated areas, submodule types are available
that occupy this process data and allocate no data area themselves.
The name of these submodule types contains the "-" character plus the quantity of
information used by the submodule.
Example:
The "4DE (-4 BIT I)" submodule type allocates no new data area and is
suitable for a module with 4 digital inputs, whose data should be assigned
an input data area previously allocated.
You can efficiently "package" the process data of digital inputs/outputs by using
both allocating and non-allocating submodule types.
More information on the module and submodule types!
The appendix contains a list of module types with possible submodule types and
assignment of the respective I/O modules with information about data values in
section "Module and Submodule Types of the I/O Modules".
7.6.1.1

Rules for Packaging Digital Information

Only allocated data can be processed.
If a submodule type allocates more data than immediately required, the surplus
data volume can be occupied by submodule types that allocate no data. The data
volume of these submodule types, however, cannot be greater than that previously
allocated.
The following rules apply for allocating and occupying data:
• Assignment is separate for inputs and outputs.
• The assignment takes the order into account.
I/O modules, for which non-allocating submodule types have been
configured, can only occupy data previously made available by an allocating
submodule.
• Assignment is section by section.
Once another I/O module is configured, whose submodule type allocates
input and/or output data, a new section begins. I/O modules with non-
allocating submodule types can only occupy data in the last allocating
section. The allocated data in preceding sections cannot be used
retroactively.
WAGO-I/O-System 750
750-370 PROFINET IO Fieldbus Coupler
Manual
Version 2.0.0