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<WorkspaceDirectory>\DataFiles\xio.Modbus.DatapointDefinitions.dat


The Modbus interface provides the opportunity to read and write Modbus datapoints. The current version of the NETx BMS Core Server 4.0 support the handling of Modbus discrete inputs, coils, holding registers, and input registers. 
The encoding of Modbus datapoint types is vendor-specific. To be able to deal with the different vendor-specific encoding, configuration parameters to set the swapping of Words, Double Words, and Bits are available. These parameters can be defined for each device and for each datapoint. Furthermore, it is possible to specify the endianess that is used within the device.
Note that using the correct encoding settings is at utmost importance. If these parameters are incorrect, the corresponding values of the Modbus datapoints are interpreted, stored, and displayed in a wrong way. Furthermore, it has to be considered that these parameters are affecting each other. To choose the correct parameters please refer to the manual and datasheet of the used Modbus devices.
The structure of the Modbus datapoint definition file is as follows:


' Modbus datapoint configuration file
' DeviceName;ModbusType;Address;SubDataType;Size;Description;PollingInterval;Persistent;Historical;Synchronize; Wordswap;DWordswap;Bitswap
ModbusController1;discrete input;12416;bool;1;DI 1;10;F;F;F;F;T;F
ModbusController1;coil;12417;bool;1;DO 1;10;F;F;F;;;;;
ModbusController1;input register;12418;uint16;1;AI 1;10;F;F;F;F;;;;;
ModbusController1;holding register;12419;uint16;1;AO 1;10;F;F;F;F;;;;;
Each line – except comment lines that start with ' – defines a single Modbus datapoint.

 

  Parameter  Description
1DeviceName This attribute refers to the name of the device which holds the datapoint. This name must match the device name used in the Modbus device configuration.
2ModbusType This parameter refers to the datapoint type.
3Address This attribute defines the memory address of the Modbus datapoint.
4SubDataType This identifier specifies the data type of Server Item that shall represent the Modbus datapoint.
5Size This identifier specifies the size of the Modbus datapoint (only considered if DataType is set to "string" or "wstring".
6Description This attribute can be used to specify a human-readable text that further describes the datapoint.
7PollingInterval This parameter specifies the interval that is used to poll the value of the datapoint.
8Persistent This parameter specifies whether the value of the datapoint is persistent (restored from the database after server start up ) or not.
9Historical This parameter specifies whether historical values of the datapoint are stored within the database or not.
10Synchronize If this parameter is set to "T", the value is synchronized between the main and backup server (if present). This will work only if synchronize is enabled in the NMESH configuration of the NETx BMS Core Server.
11Wordswap This parameter can be used to overwrite the Word Swap parameter of the Modbus device. If this parameter is set to "T" ("TRUE") or "F" ("FALSE"), the word swapping for this datapoint is overwritten. If this parameter is empty (or set to a value unequal to "T" or "F"), the word swapping specified in the device definition is used.
12DWordswap This parameter can be used to overwrite the Double Word Swap parameter of the Modbus device. If this parameter is set to "T" ("TRUE") or "F" ("FALSE"), the double word swapping for this datapoint is overwritten. If this parameter is empty (or set to a value unequal to "T" or "F"), the double word swapping specified in the device definition is used.
13Bitswap This parameter can be used to overwrite the Bit Swap parameter of the Modbus device. If this parameter is set to "T" ("TRUE") or "F" ("FALSE"), the bit swapping for this datapoint is overwritten. If this parameter is empty (or set to a value unequal to "T" or "F"), the bit swap specified in the device definition is used.
14Read on Reconnect If this parameter is set to "T", a read request is sent The default value is "T".
15Write Mode If not specified, the write mode that is defined within the Modbus Device Definition is used.

 

 

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