Configuring The Sm@Rt Das System; Modbus Function Codes - Siemens Sm@rt DAS User Manual

Chapter 4
Communications

Configuring the Sm@rt DAS System

There are two methods of changing settings on the Sm@rt
DAS controller:
To configure with HMI – refer to Chapter 3
To configure with MODBUS communication

MODBUS function codes

Table 4.1 shows MODBUS function codes used to access data
from devices. For Sm@rt DAS, Code 03 is used to read holding
registers and Code 16 is used to write the holding registers.
Code Description
01 Read coil status
02 Read input status
03 Read holding registers
04 Read input registers
05 Force single coil
06 Preset single register
10 Write multiple registers
15 Force multiple registers
16 Preset multiple registers
Table 4.1: Common MODBUS function codes
13