Endress+Hauser EngyVolt RV12, Руководство по эксплуатации

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Appendix EngyVolt RV12
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Field name Example (Hex)
Error check Low 1B
Erorr check High 38
11.4.9 Holding registers
Read holding registers
MODBUS Protocol code 03 reads the contents of the 4X registers.
Example: The following query will request the prevailing ‘Demand Time’:
Field name Example (Hex)
Slave address 01
Function 03
Starting address High 00
Starting address Low 00
Number of points High 00
Number of points Low 02
Error check Low C4
Error check High 0B
Data must be requested in register pairs i.e. the “Starting Address“ and the “Number
of Points” must be even numbers to request a floating point variable. If the “Starting
Address” or the “Number of points” is odd then the query will fall in the middle of a
floating point variable the product will return an error message.
The following response returns the contents of Demand Time as 1, But see also “Exception
Response” later.
Field name Example (Hex)
Slave address 01
Function 03
Byte count 04
Data, High Reg, High Byte 3F
Data, High Reg, Low Byte 80
Data, Low Reg, High Byte 00
Data, Low Reg, Low Byte 00
Error check Low F7
Error check High CF
Write holding registers
MODBUS Protocol code 10 (16 decimal) writes the contents of the 4X registers.
The following query will set the Demand Period to 60, which effectively resets the Demand
Time:
Field name Example (Hex)
Slave address 01
Function 10