I/O Terminal /
EXTENDED FUCNTIONS
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7.4 Multi-Configuration
Mode
Multi-configuration mode can be used for the following types of application. A more extensive
consideration, considering, in particular, the various implementation levels of the Bus
Coupler, is given in the Requirements of a production machine.
7.4.1 Creating a DP Configuration for Various Implementation Levels
If it is desired to use one PLC program to control different implementation levels of a process,
it can be valuable to work with the same DP configuration in spite of differences between the
implementation-specific terminal configurations. In this way the address offsets in the process
image do not change, nor will the general DP configuration of the Profibus DP master have to
be saved again with every new implementation level. With the multi-configuration mode it is
now possible to define a maximum configuration for the Bus Coupler, and in this case it will
only be necessary to disable those terminals that are not present in accordance with the
current implementation level.
7.4.2 Reserved Bus Terminals
Because all the analog terminals are configured first in the DP configuration, before the digital
terminals, the consequence of inserting analog terminals at a later stage is that the address
offsets of the digital terminals are shifted. The insertion of a digital terminal within the existing
terminal structure (which can, for instance, be useful if digital terminals with different input
voltages are used) also has the consequence that the offsets of the digital terminals that
follow it are shifted. If a digital terminal is inserted before the end terminal however, the offset
of the existing terminals are not shifted. With multi-configuration mode it is now possible to
configure additional terminals as reserves at any location within the terminal structure.
7.4.3 Assign Bus Terminals to Freely Choose Process Image Addresses
Because digital terminals are always grouped into bytes, which means that the smallest DP
configuration module is an 8-bit module, a difficulty arises when the associated terminals are
to be distributed over a number of bytes in the PLC process image. This is because in the
PLC it is usually only possible to assign addresses for each DP configuration module. With
multi-configuration mode it is now possible to configure additional digital terminals as
"dummy" terminals at any desired locations, enabling the address offsets of the other
terminals to be shifted in the PLC process image.
7.4.4 Setting the Multi-configuration Mode
Multi-configuration mode is activated via the UserPrmData:
Byte
Bit
Description
3
4
1: Multi-configuration mode is active
7.4.5 Rules for Multi-configuration Mode
Multi-configuration mode requires a few additional rules to be observed, in addition to those
for standard configuration:
Only one DP module may be configured for each analog terminal
