V02.00 | 2019/10
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PROFINET naming convention
The names are assigned via DCP. The device name must meet the requirements of the Domain
Name System (DNS) (see below). The device name is checked for correct spelling during input.
NOTE
The maximum length of the device name is 255 characters according to the specific-
ation. In a Step7 or TIA Portal environment, however, only names with a maximum
length of 127 characters are accepted.
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All device names must be unique.
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Maximum name size: 255 or 127 characters (a…z, 0…9, “-” or “…”)
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Do not use capital letters.
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The name must not begin or end with "-".
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Do not use special characters
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The name must not begin with 0…9 or "port-xyz" (xyz = 0…9).
8.6.4
FSU – Fast Start-Up (prioritized startup)
FSU - Fast Start-Up is not supported by device.
8.6.5
MRP (Media Redundancy Protocol)
The device supports MRP.
MRP is a standardized protocol according to IEC 62439. It describes a mechanism for media re-
dundancy in ring topologies. With MRP, a defective ring topology with up to 50 nodes is detec-
ted and reconfigured in the event of an error. With MRP a trouble-free switch-over is not pos-
sible.
A Media Redundancy Manager (MRM) checks the ring topology of a PROFINET network defined
by the network configuration for functionality. All other network nodes are Media Redundancy
Clients (MRC). In the error-free state, the MRM blocks normal network traffic on one of its ring
ports, with the exception of the test telegrams. The physical ring structure thus becomes a line
structure again at the logical level for normal network traffic. If a test telegram fails to appear, a
network error has occurred. In this case, the MRM opens its blocked port and establishes a new
functioning connection between all remaining devices in the form of a linear network topo-
logy.
The time between ring interruption and recovery of a redundant path is called reconfiguration
time. For MRP, this is a maximum of 200 ms. Therefore, an application must be able to com-
pensate for the 200 ms interruption. The reconfiguration time always depends on the Media
Redundancy Manager (e.g. the PROFINET PLC) and the I/O cycle and watchdog times set here.
For PROFINET, the response monitoring time must be selected accordingly > 200 ms.
It is not possible to use Fast Start-Up in an MRP network.
8.6.6
User data for acyclic services
The acyclic data exchange is by using via Record Data CRs (Communication Relation). Via these
Record Data CRs the reading and writing of the following services is realized:
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Writing of AR data
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Writing of configuration data
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Reading and writing of device data
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Reading of diagnostic data
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Reading of I/O data
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Reading of Identification Data Objects (I&M functions)
