BONFIGLIOLI Vectron Agile, Communications Manual

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Modbus Agile 27 02/2011
Protocol
7.3.1 Function Code 3, Read 16-Bit or 32-Bit-Parameter
This function code is used to read the value of 16 Bit or 32 Bit parameters in the inverter.
Request 16 Bit parameter read:
Start Frame (RTU oder ASCII mode)
Address 1 Byte 1 – 0xF7 (=247)
Function Code 1 Byte 0x03
Start Address (Data Set / Para-No.) 2 Bytes 0x0000 – 0x963F
No. of Registers 2 Bytes 0x0001
CRC or LRC & Endframe
Response 16 Bit parameter read:
Start Frame (RTU oder ASCII mode)
Address 1 Byte 1 – 0xF7 (=247)
Function Code 1 Byte 0x03
No. of Bytes 1 Byte 0x02
Register Value (Parameter Value) 2 Bytes 0 – 0xFFFF
CRC or LRC & Endframe
Request 32 Bit parameter read:
Start Frame (RTU oder ASCII mode)
Address 1 Byte 1 – 0xF7 (=247)
Function Code 1 Byte 0x03
Start Address (Data Set / Para-No.) 2 Bytes 0x0000 – 0x963F
No. of Registers 2 Bytes 0x0002
CRC or LRC & Endframe
Response 32 Bit parameter read:
Start Frame (RTU oder ASCII mode)
Address 1 Byte 1 – 0xF7 (=247)
Function Code 1 Byte 0x03
No. of Bytes 1 Byte 0x04
Register Value (Parameter Value) 4 Bytes 0 – 0xFFFFFFFF
CRC or LRC & Endframe
Exception Response:
Start Frame (RTU oder ASCII mode)
Address 1 Byte 1 – 0xF7 (=247)
Error Code 1 Byte 0x83
Exception Code 1 Byte 2, 3 or 4
CRC or LRC & Endframe
Start Address
This field is used to store the parameter number and data set number. The parameter number ranges
from 0 - 1599 and is stored in the lower 12bits; the data set number ranges from 0 – 9 and is stored
in the upper 4 bits.
Example: Parameter 372 (hex. 0x174), data set 2 (hex. 0x2) is stored as hex. 0x2174.
Start Address
Data Set
Parameter number
Bits 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
For the above example:
Hex. 0 0 1 0 0 0 0 1 0 1 1 1 0 1 0 0
Bin. 2 1 7 4
No. of Registers
This field is used to store the no. of parameters to be written. The value must always be 1 as it is only
possible to write one parameter at a time.
Byte Count
This field is set to
• 2 for 16 Bit parameters.
• 4 for 32 Bit parameters.
Register Value
This field is contains the 16-bit or 32-bit parameter value.
Note:
Parameter values with decimal places are transferred without the decimal point. Depending on the
number of decimal places, the values are multiplied by 10, 100 or 1000.
Example:
A current value of 10.3A is transmitted. The numerical value actually transmitted is 103, which corres-
ponds to 0x67 in HEX format.
Exception Code
The following exception codes can occur:
2 ILLEGAL DATA ADDRESS
− No. of Registers field not equal to 1.
− Parameter unknown
3 ILLEGAL DATA VALUE − No. of bytes in the data field too small or too large
4 SLAVE DEVICE FAILURE − Error on reading the parameter
Exception Codes are described in detail in Chapter 7.3.9 "Exception Codes".
Examples:
16 Bit 32 Bit
Modbus RTU
9.1.1.1 9.1.2.1
Modbus ASCII 9.2.1.1 9.2.2.1