# Serial Read This function block reads the latest line from a serial connection (non-blocking) and converts it to a chosen data type. It is designed to be resilient to stale or malformed input by returning a user-defined default when needed. ## đŸ“Ĩ Inputs * `Enable` Boolean input socket that enables or disables reading. * `ConnId` Generic input socket that selects which serial connection to read from (connection identifier). ## 📤 Outputs * `Data` Generic output socket that emits the latest converted value (or the default value when stale/failed). ## 🕹ī¸ Controls * `Stale timeout (s)` Text input that sets how long to wait for a new line before treating the reading as stale. * `Data Type` Dropdown to choose the conversion type for incoming lines. Available options: `String`, `Int`, `Float`, `Boolean`, `HexInt`, `Bytes`. * `Default (on stale/parse fail)` Text input that provides the fallback value returned when no fresh data is available or conversion fails. For `Bytes` enter hex characters (e.g., `AA55`). ## đŸŽ¯ Features * Non-blocking read of the latest available line. * Stale detection so old lines are not forwarded indefinitely. * Multiple conversion types with a configurable fallback value. * Simple inputs and outputs to integrate into larger scenarios. ## 📝 Usage 1. Provide a connection identifier to `ConnId` that refers to an active serial connection. 2. Use `Enable` to start or stop reading without removing the block. 3. Set `Stale timeout (s)` to define how fresh the incoming data must be. 4. Choose the desired `Data Type` to convert incoming lines. 5. Define `Default (on stale/parse fail)` to control what the block outputs when there is no fresh or parseable data. 6. Consume the output from `Data` in subsequent blocks for logging, visualization, or publishing. ## 📊 Evaluation * When enabled, the block attempts to read the latest line from the selected connection. * If no new line arrives within the configured stale timeout, the block emits the configured default. * If conversion to the selected data type fails, the block emits the configured default. * For `Bytes` type, the block treats the default as hexadecimal text. ## 💡 Tips and Tricks * Use `Debug Input` to log or inspect raw results during development. * Forward serial readings to `Data to JSON` or `CSV Export` for structured logging or batch export. * Publish processed values with `MQTT Publish` or send them to a web service using `REST API - Post`. * Store values for later use with `Data Write Local` or `Data Write Global` and retrieve them with the corresponding read blocks. * Plot numeric data in real time using `Scope` to observe trends or anomalies. * Combine with `Logic Input` or comparison blocks to trigger actions based on incoming values (for example, alarm when a numeric reading exceeds a threshold). ## 🛠ī¸ Troubleshooting * If no data appears on `Data`, verify the provided `ConnId` refers to an active connection. * If output is always the default, increase `Stale timeout (s)` or ensure the source is actively sending lines. * If conversion fails for a numeric or boolean type, check the raw text format from the device and adjust the default accordingly. * For `Bytes` type, ensure the default is provided as valid hexadecimal characters (no spaces or non-hex chars). --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://docs.augelab.com/function-blocks/input-output/communication/serial-read.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.