Delta RMC151 - Manual (Page 495)

6 Communication
Indirect Data Map
The only data guaranteed to be consistent are variables, if they are placed first in the
Incoming Data area of the Indirect Data Map. The size of guaranteed consistent data
depends on the loop time:
• 1 ms or longer loop time: The first 100 registers will be consistent if they are
all variables.
• 500 us loop time: The first 50 registers will be consistent if they are all
variables.
• 250 us loop time: The first 25 registers will be consistent if they are all
variables.
As soon as the first register is encountered that is not a current or initial variable
register, the guarantee for data consistency no longer applies. Remaining registers in
the I/O block will be processed as time allows on subsequent motion loops, taking up
to a maximum of 10 ms. For this reason, variables should be included first in the
Incoming I/O Data Area of the Indirect Data Map in order to ensure their consistency.
Notice that if commands are mapped to the Indirect Data Map, the commands will all
be submitted at the same time, after all values have been written.
Other Locations
No data consistency is guaranteed when consuming in other areas (such as axis
parameters). The entire write can take as long as 10 ms, with the write being deferred
to the next control loop at any point as required to meet loop time requirements.
6.8.10.7.4. Using PROFINET Record Data
PROFINET defines Record Data in addition to the cyclic I/O data exchange. The PLC can read
or write these records using RDREC and WRREC or similar function blocks. Each data record
within a PROFINET device is addressed through the Slot, Subslot, and Index. The RMC
supports three types of data records: fixed, custom, and PROFINET-specific. Only the first two
are typically of interest to RMC users.
PROFINET allows the caller to specify the length of the data being read, but does not specify a
starting offset within the given data record. Therefore, the PLC can only read or write starting
at the beginning of a data record.
Fixed Data Records
The RMC defines one data record for each RMC register file with the index of each match
the number of the register file. Fixed data records are addressed as Slot 0, Subslot 1, and
Index of 7-255:
Index Starting Address Description
7 %MD7.0 Contents of RMC register file 7
8 %MD8.0 Contents of RMC register file 8
: : :
255 %MD255.0 Contents of RMC register file 255
For a list of the register files and their content see the RMC70 Register Map or the
RMC150 Register Map.
Notice that because PROFINET always starts its reads and writes at the beginning of the
data record, fixed data records can only be used to read or write starting at the beginning
of an RMC register file. Custom Data Records get around this limitation.
Custom Data Records
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