Modbus TCP - Instance & item setup
Instance
The parameters specific to the Instance setup are related to the initial connection with the Modbus TCP server
| Parameter | Description |
|---|---|
| Address | The IP address of the Modbus Server |
| Port |
Port of the Modbus Server Default: 502 |
| Server ID |
Server ID of the Modbus Server Default: 1 |
| Max Read Registers |
Maximum amount of registers read in a single message Note: Some servers allow for specific numbers of registers read in a single message. If this is exceeded, the connection could be refused Default: 123 |
| Write Preset |
Chooses which function code used for writing
Default: Multiple registers |
| Endianness |
Word order / Endianness is documented in this article Default: Big endian |
| Byte Order |
Byte order is documented in this article Default: First byte high |
| String endianness |
Word order / Endianness for strings Default: Big endian |
| String byte order |
Byte order for strings Default: First byte high |
Item
| Parameter | Description |
|---|---|
| Register |
Registers are the addressing syntax used by Modbus. Depending on the register type, chosen below, there are two ways of addressing. Both 5-digit and 6-digit registers are supported When Register Type is Auto Here we use the full address of the register. The first Holding Register will be 40001 or 400001 When Register type is Holding Register (or any other type) Here SIA Connect will automatically fill out the full register syntax. The first Holding Register will be 0 |
| Register Type |
Register type defines the method of auto-filling the full register syntax
|
| Type |
Chooses both the amount of registers being read, and how they are parsed as data. If a tag is over 1 register, this is where it is chosen. Nothing changes on the addressing syntax, as it is automatically handled by SIA Connect |
| Floating Point Precision | Defines the decimal precision of Floats |