Comtrol IOLM Modbus TCP - Manual (Page 8)

10 - Chapter 1. Modbus/TCP Interface IO-Link Master Modbus/TCP Reference Manual: 2000590 Rev. A
Multiple Port Process Data (PDI and PDO) Access via Modbus TCP
1.3. Multiple Port Process Data (PDI and PDO) Access via Modbus
TCP
The process data has been grouped together in order to minimize the number of Modbus messages required to
interface to the IO-Link master. The PDI and PDO data for multiple ports can be received or transmitted by
one message.
Modbus
Holding
Register
Address
(Base 1)
Controller
Port 1 Access
Controller
Port 2 Access
Controller
Port 3 Access
Controller
Port 4 Access
Read
(Input)
Write
(Output)
Read
(Input)
Write
(Output)
Read
(Input)
Write
(Output)
Read
(Input)
Write
(Output)
Read
(Input)
Process
Data
Input
1000
(Port 1)
2000
(Port 2)
3000
(Port 3)
4000
(Port 4)
Read
(Input)
Process
Data
Output
1050
(Port 1)
2050
(Port 2)
3050
(Port 3)
4050
(Port 4)
Write
(Output)
Process
Data
Output
1050
(Port 1)
2050
(Port 2)
3050
(Port 3)
4050
(Port 4)