KUNBUS-COM EtherCAT
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6.4 Memory of the Communication Channels
The following memory registers contain the input and output data of
the communication channels. Cyclical process data is written there or
read from there.
The Data Broker distributes this data cyclically according to the
Mapping entries. At the same time, the input data of the producers is
assigned to the output data of the consumers.
The data can be read from the input registers at any time via the
Modbus protocol. It is only possible to write to input registers via the
respective communication channels (only in the case of SDI is this
the Modbus communication itself, of course). The initial value in the
input registers is 0 until a register is written with process data.
Output registers that are not written by the Data Broker also contain
the initial value 0 regardless of the setting for the drop-off value in the
event of validity periods of the source data being exceeded. Output
registers can solely be written by the Data Broker. Read access is
not possible via Modbus, however.
The DPR input and output registers are only available in DPR mode.
Otherwise, access is not possible and any attempt to do so (e.g.
reading via Modbus or access by the Data Broker) will result in an
error.
0x1001 Input SSC
Modbus Register
0x1001-0x1080
Coil Address
0x0001 – 0x0800
Value Range
-
Initial value
0x00
Number of bytes available
256
Permanently stored
No
Access
Read Only
Memory Register