I/O Mapping an I/OBus Network with Modsoft
248 870 USE 101 10 V.2
Supporting an I/O Map for an I/OBus Network
Introduction The 171 CCS 760 00 and 171 CCC 760 10 Processor Adapters have an I/OBus
communication port that enables them to control and communicate with network
slave I/O.
If you are using I/OBus to control network I/O, you need to write an I/O Map in your
configuration. This section describes the configuration parameters required to
support an I/O Map for I/OBus.
I/O Map
Reserved Words By default, 512 words are reserved for I/O Mapping. This may or may not be the
appropriate memory allocation to support your I/OBus network. A rule of thumb for
roughly estimating the number of words required for I/O Mapping is:
l16 words for overhead
l10 words/module on the network (including both the local and the network I/O)
The idea behind adjusting the memory size is to allow you to completely I/O Map
your network while preserving as much user memory as possible for your
application program.
Required
Settings Be sure that the following parameters are set on the Configuration Overview
screen:
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Parameter Setting
Processor type 12.0 for a 171 CCS 760 00
Processor Adapter
18.0 for a 171 CCC 760 10
Processor Adapter
Number of segments 2
I/O Map reserved words Enough to support your I/O map