Endress+Hauser EngyVolt RV12, Руководство по эксплуатации

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Appendix EngyVolt RV12
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11.4.11 Exception codes
Table of exception codes
Exception code Modbus protocol name Description
01 Illegal function The function code is not supported by the product.
02 Illegal data address Attempt to access an invalid address or an attempt to
read or write part of a floating point value.
03 Illegal data value Attempt to set a floating point variable to an invalid
value.
05 Slave device failure An error occurred when the instrument attempted to
store an update to its configuration.
11.4.12 Diagnostics
MODBUS Protocol code 08 provides a number of diagnostic sub-functions. Only the
“Return Query Data” sub-function (sub-function 0) is supported on EngyVolt devices.
Example:
The following query will send a diagnostic “return query data” query with the data
elements set to Hex(AA) and Hex(55) and will expect these to be returned in the response:
Field name Example (Hex)
Slave address 01
Function 08
Sub-function High 00
Sub-function Low 00
Data byte 1 AA
Data byte 2 55
Error check Low 5E
Error check High 94
Exactly one register of data (two bytes) must be sent with this function.
The following response indicates the correct reply to the query, i.e. the same bytes as the
query.
Field name Example (Hex)
Slave address 01
Function 08
Sub-function High 00
Sub-function Low 00
Data byte 1 AA
Data byte 2 55
Error check Low 5E
Error check High 94