Omron E5CN-H Communications Manual

Modbus
5.4 Detailed Description of the Services
5-9
5.4 Detailed Description of the Services
■ Variable Read, Multiple
To read from the variable area, set the required data in the command
frame, as shown in the following diagram.
Command Frame
Name Description
Slave address Specify the E5CN/AN/EN-H’s unit number.
The unit number can be set between H’01 and H’63 hexadecimal (1
to 99 decimal).
Function code The Read Variable Area function’s function code is H’03.
Read start address Specify the address containing the data to be read.
See SECTION 6 Communications Data for Modbus for details on
addresses.
Number of elements Four-byte Mode
Specify 2 times the number of setting data items as the number of
elements to be read. The setting range for the number of elements is
H’0002 to H’006A (2 to 106).
When H'006A is set, 53 items of setting data can be read.
Example: When reading 2 items of setting data, set the number of
elements to H’0004.
Two-byte Mode
Specify the number of setting data items to be read as the number of
elements.
The setting range for the number of elements is H'0001 to H'006A (1
to 106).
When H'006A is set, 106 items of setting data can be read.
Example: When reading two items of setting data, set the number of
elements to H'0002.
CRC-16 This check code is calculated with the data from the slave address to
the end of the data.
For details on the CRC-16 calculation, see CRC-16 Calculation
Example in 5.1 Data Format on page 5-3.
CRC-16
11
H'03
22
Number of
Elements
2 bytes
Slave
address
Function
code
Read
start address

Omron E5CN-H Specifications

General

Brand	Omron
Model	E5CN-H
Category	Controller
Language	English