---
title: OSI Agent
slug: bhdo-v1/osi-agent
createdAt: 2023-05-05T12:39:09.000Z
---

:::hint{type="info"}
**Note**: This driver is available for Belden Horizon Data Operations version 3.5.2 and later. 
:::

Review the following information for setting up and configuring the OSI Agent driver. 

:::hint{type="warning"}
**Important**: 

- The DH Historian Agent can only have one OSI PI agent and one OSI PI server connection with one username/password configured for the OSI PI server.
- The username/password in the DeviceHub configuration is to access the DH Historian Agent, not the OSI PI server.
- If you would like to manage access to tags/data being sent through the OSI PI agent and server, you can set up multiple Belden Horizon Data Operations connections through the NATS connector. See [Set Up Edge Cascading with the NATS Connector](docId\:SoAZsV-GRGbgbL6nsPmF9) to learn more.  
:::

# Set Up the OSI Agent

See [Set Up the OSI Agent](docId:8A914l2f7KcuLTzNhFDJ5) to review how to set up and configure the OSI Agent driver. 

# OSI Agent Driver Settings in Belden Horizon Data Operations

If you review or edit the settings of the OSI Agent device, refer to the following parameters. 

| Parameter        | Value                                                                                                                                                                                            |
| ---------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| **Type**         | OSI                                                                                                                                                                                              |
| **Driver**       | OSI Agent                                                                                                                                                                                        |
| **Network Port** | The port configured in the DH Historian Agent. The default value is 4777.                                                                                                                        |
| **Interface**    | You have the option of selecting the interface for accepting client connections. The default value is 0.0.0.0, which means using all network interfaces for accepting connections from clients.  |
| **User**         | The username configured in the DH Historian Agent.                                                                                                                                               |
| **Password**     | The password configured in the DH Historian Agent.                                                                                                                                               |

If you [Add Tags](docId\:Wpe2HMXelARLBnhWbuChY) in Belden Horizon Data Operations, select the **R** register name, and then refer to the following supported data types and tag parameters.  

## Supported Data Types

- `uint32`
- `uint64`
- `float64`
- `string`
- `byte[]`
- `float32[]`
- `bool`
- `byte`
- `float64[]`
- `string[]`
- `uint16`
- `int64`
- `uint16[]`
- `sbyte`
- `int16`
- `int16[]`
- `int32[]`
- `int64[]`
- `uint64[]`
- `float32`
- `bool[]`
- `uint32[]`
- `int32`
- `sbyte[]`

## Tag Parameters

- **Name**: Select **R**.  
- **Value Type**: Select a value type. 
- **Tag Name**: Enter a name for the tag.
- **Description** (Optional): Enter a description for the tag.  
- **Tag Formula**: Enter a formula for the tag to process the generated data. Two variables are permitted: `value` (current tag value) and `timestamp` (current tag UNIX time in milliseconds). The following math functions are available:
  - sin
  - cos
  - sqrt
  - tan
  - power
  - log
  - exp
- **Only Publish on Change of Value**: Select the checkbox to customize NATS messages to be published only when the *value *parameter changes from a previous value to a new one. *Change of Value* only applies to boolean, numeric (such as int or float), and simple string data types. It does not apply to complex types, such as JSON or array. Poll-once topics will not be affected by *Change of Value* settings. These topics will still only see a single message.
- **Meta Data**: Metadata summarizes basic information about data. This feature allows you to define key-value pair data for the device output payload later on. It can then be used to find, use, and reuse particular instances of data.