# Serial Connect This function block opens and manages a serial (COM) connection. Use it to connect to serial devices, monitor connection state, and expose a connection identifier for other blocks to reference. ## đŸ“Ĩ Inputs This function block does not have any inputs. ## 📤 Outputs `ConnId` Unique identifier for the opened serial connection. Use this value to reference the connection from other blocks. `Connected?` Boolean flag that indicates whether the serial connection is currently active. ## 🕹ī¸ Controls `Port` COM port name to connect to (for example COM3). `Baud` Communication speed (for example 115200). `Read timeout (s)` Time in seconds to wait for read operations. `Line delimiter` Select the line ending used by your device (LF / CRLF / CR). `AutoReconnect` Switch that enables automatic reconnection when the connection drops. `Reconnect interval (s)` Interval between reconnection attempts when auto-reconnect is enabled. `Idle disconnect (s)` Time of inactivity after which the connection will be closed automatically to free the port. ## 🎨 Features * Automatic connection management: opens a connection with the configured parameters and keeps the `ConnId` available to other blocks. * Auto-reconnect: optionally retries when the device becomes unavailable. * Idle disconnect: closes the port when unused to avoid locking the device for other applications. * Human-readable settings: select newline convention and tune timeouts to match the connected device. ## 📝 Usage Instructions 1. Set the `Port` and `Baud` values to match your device. 2. Configure `Read timeout (s)` and `Line delimiter` according to your device protocol. 3. Toggle `AutoReconnect` and set `Reconnect interval (s)` if you want the block to recover from disconnections automatically. 4. Adjust `Idle disconnect (s)` to let the block close the port when not in use. 5. Run the scenario. The block will open the connection and output `ConnId` and `Connected?`. Use the `ConnId` in other communication blocks that accept a connection reference. ## 📊 Evaluation When evaluated, the block ensures a serial connection exists with the current settings. If settings change, the previous connection is released and a new one is created. The outputs reflect the active connection id and whether the connection is currently established. ## 💡 Tips and Tricks * Use `Led Output` to visually reflect the `Connected?` state in your UI. * Use `String Input` or `Number Input` and `String Merge` to craft commands to send over the serial link. * Use `Data Write Global` / `Data Read Global` to share the `ConnId` or serial results with other parts of your scenario without direct wiring. * Feed serial data into `Data to JSON` or `CSV Export` to log communication for later analysis. * Forward parsed data to remote systems with `MQTT Publish` or `REST API - Post` for cloud integration or monitoring. * Use `Debug Input` to inspect messages while developing your serial workflow. * Combine with `Send Mail` to trigger email alerts when connection drops or when specific messages arrive. ## 🛠ī¸ Troubleshooting * If `Connected?` remains false: verify the device port and baud settings match the device; check device drivers and OS device manager. * If you cannot open the port: make sure no other application is using the same COM port. Close other programs or enable idle disconnect in those systems. * If lines appear truncated or merged: try a different `Line delimiter` setting or increase `Read timeout (s)`. * If frequent disconnects occur: enable `AutoReconnect` and increase `Reconnect interval (s)` to give the device time to recover. * If unexpected characters appear: confirm baud rate and parity settings with the device documentation and adjust accordingly. --- # 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-connect.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.