Omron E5CC Communications Manual page 89

Response Frame
Slave Function
address
1
Name
Slave address
Function code
Byte count
Read data
CRC-16
Response Code
Function code
'
H 83
'
H 03
Reading Undisplayed Parameters
It is possible to read the parameters that are not displayed due to display settings as well as the
parameters that are never displayed in the Controller.
• Example Command and Response
The following example shows the command and response when reading the process value (slave
address: H'01).
Process Value in 4-byte Mode
• Address: H'0000; Read data: H'000003E8 (100.0 °C)
Command:
Response:
Process Value in 2-byte Mode
• Address: H'2000; Read data: H'03E8 (100.0 °C)
Command:
Response:
E5@C Digital Temperature Controllers Communications Manual (H175)
Read data (for the number of
Byte
code count
H'03
0 to 212 (2 × 106)
1 1
The value from the command frame is entered as-is.
This is the received function code.
When the function ended normally, the function code is left as-is. When an error
occurred, the hexadecimal value of H'80 is added to the function code to indicate
that the response is an error response.
Example: Received function code = H'03
Function code in response frame when an error occurred = H'83
Contains the number of bytes of read data.
Contains the number of setting data items that were read.
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, refer to CRC-16 Calculation Example in 4-1-1
Command Frame on page 4-2.
Error code
'
H 02
'
H 03
---
01 03 00 00 00 02
01 03 04 00 00 03 E8
01 03 20 00 00 01
01 03 02 03 E8
4 Modbus Communications Procedure
CRC-16
elements)
Description
Error name
Variable address The read start address is incorrect.
error
Variable data error The number of elements exceeds the
allowed range.
Normal completion No errors were found.
C4 0B(CRC-16)
FA 8D(CRC-16)
8FCA(CRC-16)
B8 FA(CRC-16)
2
Cause
4
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