Siemens MindConnect Nano System Manual page 61

Parameter Description
Function type - depends on the type of the data (see manual of the Modbus device).
1: Read Coils,
Function 2: Read Inputs,
Type 3: Read Holding Registers,
4: Read Input Registers
. Currently function codes 1..4 are supported.
Slave
Address/Slave number of the Modbus device.
Number
Start
Start address (offset) of the data.
Address
Quantity Quantity of data to be read.
You can choose the following variable types of the Modbus data to be read:
1: char : 8 bits,
2: unsigned char : 8 bits,
3: short : 16 bits,
4: unsigned short : 16 bits,
VariableType
5: long : 32 bits,
6: unsigned long : 32 bits,
7: float : 32 bits,
8: double : 64 bits,
9: ascii-text : 8 bits / char
Real type - determines, if the registers of real values have to be processed in reversed
order.
0: Normal order,
Real Type 1: Reversed order,
2: Byte swap order,
3: Word swap order,
Real types 2 and 3 are available from V03.04.02.01.
It determines in which byte order format the read value will be processed (default: 0)
0: Normal order (big-endian)
1: Reversed order (little-endian byte swap)
Integer Byte
2: Byte swap order (big-endian byte swap)
Order
3: Word swap order (little-endian)
Note: Integer byte order is available for 16 bits and 32 bits variable types only, and it is
supported for the version starting from MindConnect Nano V03.04.02.13.
Response
Address Offset of the data to return in register units.
Offset
Response
Quantity of the returned data. Only for string data a value greater than 1 is supported.
Quantity
61
4.4 Overview of Modbus TCP protocol for MindConnect Nano
Configuring protocols
MindConnect Nano
System Manual 7/2023