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ifm
Device Manual IO-Link Master with Modbus interface CabinetLine 8 Ports IP 20 (AL1940)
05 / 2018
Appendix
Modbus
>
Request channel
10893
Register
Contents
Bits 8-15
Bits 0-7
500
Port No.
501
Index
502
Subindex
503
Command
User ID
504
Data Length (Number of Bytes)
505
Data (byte 1)
Data (byte 0)
...
...
...
521
Data (byte 33)
Data (byte 32)
Legend:
[Port No.]
Number of the IO-Link port
1 Word
0x0001
Port X01
0x0002
Port X02
...
...
0x0008
Port X08
[Index]
Index of the IO-Link object
1 Word
0x0000...0xFFFF
[Subindex]
Subindex of the IO-Link object
1 Word
0x0000...0xFFFF
[Command]
Command number
1 byte
0x01
Read
0x02
Write
[User ID]
ID to identify the command
1 byte
0x00...0xFF
[Data Length
(Number of
Bytes)]
Number of bytes that contain relevant user data
(is only evaluated for Command = 0x02)
1 Word
0x0000
0 bytes
...
...
0x0022
34 bytes
[Data (Byte n)]
user data
n bytes
per byte: 0x00 ... 0xFF