
2.CYCLIC TRANSMISSION DESCRIPTION B-63434EN/02
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NOTE
1 As shown in the above example, the area specified by
Pa46 (area 2 static allocation data size (in words))
can contain the local node transmit data area. In
this case, the corresponding PMC area can be
specified for Pa40 (allocation address (for DO)) to
allocate no wasted PMC area.
To make such a setting, however, carefully set Pa40
(allocation address (for DO)) not to duplicate PMC
area setting.
2 Node information can also be changed dynamically
with static DI data allocation of common memory
area 2. When node information is changed,
however, the DO offset is also changed. To change
only the node information, carefully change the
setting not to change the DO offset.
3 Information on other nodes is 4 bytes in size.
So, for an area in the R area to be allocated for DI,
allocate an area 4 bytes larger than the value set in
Pa46 (area 2 static allocation data size (in words)).
When the user program handles DI data in area 2,
the data at the address 4 bytes shifted from the
address set in Pa42 (allocation address (for DI)) is
handled.
4 There are the following restrictions on static DI data
exchange:
- When a value of 0 is specified for Pa46 (area 2 static
allocation data size (in words)), DI data exchange
with dynamic allocation is performed.
- If a negative value is set in Pa42 (allocation address
(for DI)), transfer of information on other nodes and
DI data exchange are not performed.
- If a negative value is set in Pa43 (area 2 data
exchange condition allocation address), transfer of
information on other nodes are not performed.
- If a negative value is set in Pa44 (switch flag
allocation address), node information cannot
dynamically be changed.
2.2.2.3 Nodes information