Examples Of Data Transmission; Integer Values - ECOLAB Versatronic Modbus Beschreibung

3.6

Examples of data transmission

The function 0x03 or 0x04 (writing of n words) is used to extract integers, floating-point
values and text values.
Data request
Slave address
1 byte
Integer values are transmitted via the Modbus in the following format:
The high byte first, followed by the low byte.
Response
Slave address
1 byte
3.6.1

Integer values

Example
In this example, the value of the maximum output level will be read out from parameter set
1 of controller channel 1 at address 0x13C1 (
maximum output level' on page 60).
The value here should be "100" (word value 0x0064).
Data query:
01
Slave
Response (values in Modbus floating-point format):
01
Slave
Function 0x03 oder
address First word
0x04
1 byte 2 bytes
Function 0x03 or
Number bytes read
0x04
1 byte 1 byte
03 13 C1
function Address of 1st word Number of words
03 02
function Bytes read
21
Modbus protocol description
Number of words
2 bytes
Word value(s)
x bytes
Ä Chapter 8.1.24 'Controller parameter
00 01
00 64
Integer value
417102397 Rev. 1-10.2019
Checksum CRC
2 bytes
Checksum CRC
2 bytes
D1 72
CRC
B9 AF
CRC