4-4-4 Echoback Test - Omron E5C-T Series Communications Manual

4 Modbus Communications Procedure

4-4-4 Echoback Test

Command Frame
Slave
Function
address
1
Response Frame
Slave
Function
address
1
Note: When the command is executed normally, the response returns the same data sent in the command.
(1) Test Data
Enter any 2-byte hexadecimal data.
(2) Response Code
Function code
'
H 88
'
H 08
(3) Example Command and Response
The following example shows the command/response for an Echoback Test command.
(In this case, the test data is H'1234.)
(In this case, the slave address is H'01.)
Command:
Response:
4 - 14
Fixed data
code
H'08 H'00 H'00
1 2
Fixed data
code
H'08 H'00
H'00
1 2
Error
code
'
H 03
---
01 08 00 00 12 34
01 08 00 00 12 34
E5C-T Digital Temperature Controllers Programmable Type Communications Manual (H186)
CRC-16
Test data
2 bytes
2
CRC-16
Test data
2 bytes
2
Name
Variable data error
A different value (not H
returned.
Normal completion No errors were found.
ED 7C(CRC-16)
ED 7C(CRC-16)
Description
' '
00, H 00) was