Honeywell CIU 888 Configuration Manual page 210

Appendix C - Redundancy
C.12.2.1 Configuring Modbus Controllers
Create Modbus Controller for different type of data inputs and outputs
based on the site requirement.
For example, for Holding Registers which are required for calculated
and measured parameters, a Modbus Controller "ANALOG" is created
as below and associated with configured Modbus Channel which is CIU
888_TCP. The IP Address 1 and IP Address 2 are configured with
Primary CIU 888's FTE A and FTE B IP address.
For example, if Primary CIU 888's FTE A IP address is 10.79.212.182
and FTE B IP address is 10.79.212.183, then configure IP Address 1 as
10.79.212.182 & IP Address 2 as 10.79.212.183. Also, configure the
port numbers as per the CIU 888 FTE A/FTE B configurations.
PLC Station ID should be configured based on the Unit ID selected for
Modbus map created in CIU 888 for Experion PKS integration. For
example, if the Modbus map for Experion PKS is created with Unit ID as
1, then PLC Station ID should be configured as 1.
ANALOG modbus controller for holding registers is shown in the figure
below.
Similarly, for Digital Inputs (or Read Discrete Inputs) "INPUT" controller
is created and for Digital Outputs (Write Coils) "OUT" controller is
created and downloaded to server.
Part No.: 4417584_Rev12 Configuration Manual
CIU 888 C - 24