User`s guide

Industrial Protocols PROFINET I/O
3-4
Addressing of I/O Data in PROFINET I/O
Based on Slot and Sub-Slots
The concept of the MOXA PROFINET switch with GSD version 2 is shown the table below. In this structure, each switch
port represents one sub-slot.
Manufacturer Information
Each PROFINET device is addressed based on a MAC address. This address is unique worldwide. The
company code (bits 47 to 24) can be obtained from the IEEE Standards Department free of charge. This
part is called the OUI (organizationally unique identifier).
Table. MOXA OUI
Bit Value 47..24
Bit Value 23..0
0
0
0
2
2
9
x
x
x
x
x
x
Company Code (OUI)
Consecutive Number
PROFINET Attributes
The PROFINET I/O connection can be configured for both cyclic I/O data and I/O parameters. I/O parameters are
acyclic I/O data. These are major setup and monitor attributes in PROFINET.
• Cyclic I/O Data
Cyclic I/O data are always sent between the PLC and Switches at the specified periodic time. These data are
transmitted almost real time. For example, status information from the Switches, and variables to be written to
the Switch would typically be part of the cyclic data.
• I/O Parameters
PROFINET I/O parameters are defined for device configuration and status monitoring. These data are useful for
infrequent data transfers, or for very large data transfers. Only transfer when needed
• Alarm
Alarms are mainly PROFINET I/O transmitted high-priority events. Alarm data are exchanged between an I/O
device and an I/O controller. Once an event triggers it, the switch will send the alarm to the PLC immediately.
Enable or disable these alarms by setting I/O parameters.