Prerequisites

• The datapoint definition must already be added to the device product.
• The device product must be of the Peripheral device type.

1. Access the End Application.
2. Go to Settings > Products (under Device Management section).
   
   
   
   
   
   
3. Select the device product for which you want to configure Modbus registry mapping. For this illustration, the device product My Peripheral Product is selected. 
   
   
   
   
4. Click Actions > Modbus Registry Mapping.
   
   
   
   
5. Select the datapoint to which you want to add the mapping and click Edit.
   
   
   
   
6. Provide the required values in the appropriate fields.
   
   

   Telemetry Name	The name used to as the parsing key once modbus registry mapping is assigned.
   Status	Enables or disables the Modbus registry mapping for the datapoint.If disabled, the modbus registry mapping will not be sent in the edge configuration.
   Address	The register address of the parameter as specified in the device's datasheet.
   Register Type	The Modbus register type corresponding to the parameter's address.
   Modbus Data Type	The data format in which the parameter value is stored in the register.
   Multiplier	The scaling factor applied to the raw register value. The default value is 1.
   Offset	A fixed value added to the scaled result to adjust the final reading. The default value is 0.
   Endianness	The byte order in which the register value is stored and transmitted.
   Access Direction	Specifies whether the gateway reads from or writes to the register.

         Learn more about each field in detail.

         

8. Click Update.
   
   
   

Bulk Modbus Registry Mapping

When multiple datapoints require Modbus registry mapping, you can import them in bulk using a JSON or CSV file.

The recommended workflow is:

1. Download a configuration file (JSON or CSV) pre-populated with the available keys and default values.
2. Edit the file with the correct mapping values.
3. Import the updated file back into the application. 

I. Downloading the modbus configuration file of the added datapoints

1. Go to the End Application.
   

2. Go to Settings > Products (under Device Management section).
   
   
   
   
   
   

3. Click on the device product for which you want to configure Modbus registry mapping. For this illustration, the device product My Peripheral Product is selected. 
   
   
   
   

4. Click Actions > Modbus Registry Mapping.
   
   
   
   

5. Click Actions > Import.
   
   
   
   

6. Select the format you want to download the configuration as:
   
   

• JSON to download a JSON file, or

• CSV to download a CSV file.
  
  
  
  

7. Click Export Current Configuration. A file of the selected format will be downloaded.  
   
   
   

The downloaded file will contain all available keys with null or default values. You will need to update the values of the corresponding keys as illustrated in the next step.

II. Updating the values in the configuration file

1. Open the JSON or CSV file in a code editor.
   
2. Provide the appropriate values, The tables below describe the accepted values for each field.

Field	Required Value	Corresponding Input	Example
telemetry_name	The parsing key of the datapoint, without the {EdgeKey} notation, as configured in the device product. The value must be in lowercase and separated by underscores.	String	"telemetry_name": "phase3_total_power"
id	The unique identifier of the datapoint as configured in the device product. The datapoint ID can only be obtained by downloading the configuration file and cannot be retrieved any other way.	Integer	"id": 6700000000203011
status	Set to enable or disable the mapping.	Enable: true Disable: false	"status": true
address	The Modbus register address for the datapoint.	Integer	"address": 4001
register_type	The type of Modbus register.	Coli Status: Coils Input Status: Discrete Holding Register: Holding Input Register: Input	"register_type": "Holding"
modbus_data_type	The data type of the register value.	Signed Integer 16: Int16 Signed Integer 32: Int32 Signed Integer 64: Int64 Unsigned Integer 16: UInt16 Unsigned Integer 32: UInt32 Unsigned Integer 64: UInt64 Float 32: Float32 Double 64: Float64 Unsigned Integer 8 MSB: UInt8_M Unsigned Integer 8 LSB: UInt8_L Signed Integer 8 MSB: Int8_M Signed Integer 8 LSB: Int8_L	"modbus_data_type": "Int32"
multiplier	A scaling factor applied to the raw register value. Defaults to 1.	Integer	"multiplier": 1
offset	A value added to the scaled result after the multiplier is applied. Defaults to 0.	Float	"offset": 0
endianness	The byte order used to read the register value.	Big Endian (AB): AB Little Endian (BA): BA Big Endian (ABCD): ABCD Mid-Big Endian (BADC): BADC Mid-Little Endian (CDAB): CDAB Little Endian (DCBA): DCBA Double Big Endian (ABCDEFGH): ABCDEFGH Double Little Endian (HGFEDCBA): HGFEDCBA Double Big Endian Byte Swap (BADCFEHG): BADCFEHG Double Little Endian Byte Swap (GHEFCDAB): GHEFCDAB	"endianness": "AB"
access_direction	The read/write permission for the register.	Read: R Write: W Read & Write: RW	"access_direction": "RW"

 Note: The 'id' value is unique for each datapoint and can be obtained only by exporting the configuration. 

Here is an example of JSON and CSV configuration files updated with the values for the following datapoints:

• phase3_active_power is mapped to address 4001 as a 32-bit signed integer with Big Endian (AB) byte order and read/write access.
  

• phase1_voltage is mapped to address 4003 as a 32-bit float with Big Endian (ABCD) byte order and read-only access.
  

• motor_torque is mapped to address 4005 as a 16-bit signed integer with Little Endian (BA) byte order, a multiplier of 10, an offset of 5, and read-only access. The mapping is currently disabled (status: false).
  

[
  {
    "telemetry_name": "Motor Torque",
    "id": 6700000000203011,
    "status": true,
    "address": 4001,
    "register_type": "Holding",
    "modbus_data_type": "Int32",
    "multiplier": 1,
    "offset": 0,
    "endianness": "AB",
    "access_direction": "RW"
  },
  {
    "telemetry_name": "Phase3 Active Power",
    "id": 6700000000203016,
    "status": true,
    "address": 4003,
    "register_type": "Holding",
    "modbus_data_type": "Float32",
    "multiplier": 1,
    "offset": 0,
    "endianness": "ABCD",
    "access_direction": "R"
  },
  {
    "telemetry_name": "phase1_voltage",
    "id": 6700000000203019,
    "status": false,
    "address": 4005,
    "register_type": "Input",
    "modbus_data_type": "Int16",
    "multiplier": 10,
    "offset": 5,
    "endianness": "BA",
    "access_direction": "R"
  }
]

telemetry_name,id,status,address,register_type,modbus_data_type,multiplier,offset,endianness,access_direction
Motor Torque,6700000000203011,true,4001,Holding,Int32,1,0,AB,RW
Phase3 Active Power,6700000000203016,true,4003,Holding,Float32,1,0,ABCD,R
phase1_voltage,6700000000203019,false,4005,Input,Int16,10,5,BA,R

III. Importing the updated configurations

1. Go back to the application, click Browse and select the updated file. The contents will be populated in the JSON/CSV display panel.
   
   
   
   
   
   
   
   
2. Click Validate and Preview. A validation summary will appear confirming whether all values are correctly filled in.
   
   
   
   
3. You can make inline edits if minor corrections are needed. 
   
   
   
   
4. You can choose to exclude/include a particular modbus registry configuration by clicking Exclude/Include under the Actions column.
   
   
   
   
5. Once you've reviewed and finalised the values, click Validate and Apply.
   
   
   
   

Note: If there are too many validation errors, update the values in the downloaded JSON/CSV file and re-import it.

See Also

Understanding Devices

Understanding Device Models

Adding and managing a device and device model