Building an RS232 Data Logger with ESPHome Building an RS232 Data Logger for PIP Inverter Protocol using ESPHome and Home Assistant In this article, we will explore the process of creating a data logger for monitoring inverter data locally. The project uses ESPHome and integrates with Home Assistant to log data from a PIP inverter protocol. Although the focus is on PIP inverter protocol, the hardware can be adapted to work with other inverter protocols that utilize RS232. Designing the Project The project began by creating a design using EasyEDA. The software allowed for careful planning and visualization of each component's connection and functionality. Once the design was finalized, it was used to create the PCB layout. PCB Design and Assembly The PCB design was then sent to JLCPCB for manufacturing. Currently, custom PCBs can be ordered for as low as $2, with new users eligible for a 60% discount coupon. After a waiting period of 7 days, the complete PCB board arrived. The assembly looked impressive, requiring only a few components to be soldered. Refining the Design An earlier prototype of the data logger was created but proved bulky. To address this, the design was refined and condensed onto a single PCB board. This not only reduced the size but also improved the overall appearance. Integrating with Home Assistant The data logger is integrated with Home Assistant to log inverter data locally. This integration allows for easy monitoring and analysis of the inverter's performance. Adaptability While this project focuses on PIP inverter protocol, the hardware is versatile and can be adapted for use with other inverter protocols that utilize RS232. However, customization of the firmware will be necessary for each specific protocol. Purchasing and Assembly For those interested in purchasing this data logger or other related products, please refer to the contact information provided. A comprehensive list of parts with purchasing links and circuit diagrams is also available for reference. Conclusion This project demonstrates a cost-effective and efficient method for monitoring inverter data locally using ESPHome and Home Assistant. The adaptable hardware design allows for use with various inverter protocols, making it an attractive solution for those seeking to monitor and analyze their inverter's performance. RS232 Logger The RS232 Logger is a type of data logging device that captures and records serial communication data transmitted through an RS-232 interface. Background The RS-232 standard, also known as EIA-232, was introduced in the early 1960s for serial communication between devices. It was widely used for connecting peripherals such as modems, printers, and terminals to computers. How it works The RS232 Logger connects to an RS-232 interface and captures the serial data transmission between devices. The logged data is then stored in a file or displayed on a screen for analysis. Applications The RS232 Logger has various applications, including:   Debugging and troubleshooting serial communication issues.   Monitoring and analyzing data transmission between devices.   Testing and validating serial communication protocols. Introduction In this article, we will explore how to build an RS232 data logger using ESPHome. ESPHome is a framework that allows you to create custom firmware for ESP32 and ESP8266 microcontrollers, making it easy to connect sensors and devices to the internet. We will use ESPHome to read data from an RS232 device and log it to a remote server. Hardware Requirements ESP32 or ESP8266 microcontroller board (e.g. NodeMCU, Wemos D1) RS232 device (e.g. serial console, GPS module, etc.) Breadboard and jumper wires Software Requirements ESPHome firmware (download from the official website) A text editor or IDE (e.g. Visual Studio Code, Arduino IDE) Step 1: Connect the RS232 Device Connect the RS232 device to the ESP32/ESP8266 board using a breadboard and jumper wires. Make sure to match the correct pins: TX (transmit) pin of the RS232 device to RX (receive) pin of the ESP32/ESP8266 RX (receive) pin of the RS232 device to TX (transmit) pin of the ESP32/ESP8266 Step 2: Configure ESPHome Create a new ESPHome project using your preferred text editor or IDE. In the `configuration.yaml` file, add the following lines: serial: - port: UART0 baud_rate: 9600 logger: level: DEBUG loggers: - serial Step 3: Write the Logger Script Create a new file called `logger.py` in the same directory as your ESPHome project. In this file, add the following Python code: import esphome import time logger = esphome.logger.getLogger() def log_data(data): logger.info("Received data: %s", data) while True: data = esphome.serial.read(1024) if data: log_data(data.decode()) time.sleep(1) Step 4: Upload the Firmware Upload the ESPHome firmware to your ESP32/ESP8266 board using the `esphome upload` command. Once uploaded, reset the board. Step 5: Test the Logger Open a serial console (e.g. `screen /dev/ttyUSB0 9600`) and connect to the ESP32/ESP8266 board. Send some data from the RS232 device, and you should see it logged in the console. Conclusion In this article, we have built an RS232 data logger using ESPHome. This project can be used as a starting point for more complex IoT projects that require serial communication. Remember to customize the baud rate and pin configurations according to your specific use case. Q1: What is ESPHome? ESPHome is an open-source framework that allows you to control and monitor your ESP32/ESP8266 boards using a YAML configuration file. Q2: What is RS232? RS232 (Recommended Standard 232) is a standard for serial communication transmission of data, commonly used in industrial and commercial applications. Q3: What is a Data Logger? A Data Logger is an electronic device that records data over time, allowing you to monitor and analyze the behavior of a system or process. Q4: Can I use ESPHome to build an RS232 Data Logger? Q5: What hardware do I need to build an RS232 Data Logger with ESPHome? You will need an ESP32/ESP8266 board, an RS232 adapter (e.g. MAX3232), and a device that sends data via RS232. Q6: How do I configure ESPHome to read data from the RS232 device? You will need to create a YAML configuration file that defines the serial component and sets up the communication parameters (e.g. baud rate, parity) for your specific RS232 device. Q7: Can I log data from multiple RS232 devices with ESPHome? Q8: How do I store the logged data? You can store the logged data on an SD card, send it to a server via HTTP or MQTT, or use a cloud-based logging service. Q9: Can I visualize the logged data in real-time? Q10: Is it possible to trigger actions based on the logged data? Rank Pioneers/Companies Contribution 1 Espressif Systems (ESPHome) Developed the ESP32/ESP8266 microcontrollers and the ESPHome framework, making it easier to build IoT projects. 2 Adafruit Industries Popularized the use of microcontrollers in DIY projects and provided extensive documentation and libraries for various platforms. 3 Arduino LLC Created the Arduino platform, making it easier for hobbyists and professionals to build interactive electronics projects. 4 SparkFun Electronics Developed various open-source hardware platforms, including the ESP32/ESP8266, and provided tutorials and resources for building IoT projects. 5 IOT-BOTS (IoT-MCU) Provided a comprehensive platform for building IoT projects using the ESP32/ESP8266, including hardware, software, and tutorials. 6 MakerFocus Developed various open-source hardware platforms, including the MakerFocus RS232 Data Logger, specifically designed for building data logging projects. 7 CircuitPython (Adafruit) Created a Python-based framework for building IoT projects on microcontrollers, making it easier to develop and deploy applications. 8 PyCom Developed the PyBoard, a range of microcontrollers that can run Python, and provided a comprehensive platform for building IoT projects. 9 MicroPython ( Damien George) Created MicroPython, a lightweight implementation of the Python programming language for microcontrollers. 10 RS Components (RS232 module) Provided a widely used RS232 module that can be easily integrated with various microcontrollers, making it easier to build data logging projects. Hardware Components ESP32/ESP8266 Microcontroller (e.g., NodeMCU, ESP32 DevKitC) RS232 to TTL Serial Converter (e.g., MAX3232, FTDI FT232RL) Breadboard and Jumper Wires Software Components ESPHome (a YAML-based firmware for ESP32/ESP8266) RS232 Protocol Library (e.g., RS232Protocol in ESPHome) Logging and Data Storage Library (e.g., Logger, FileLogger in ESPHome) Connection Diagram ESPHome Configuration # Define the RS232 serial port serial: - id: rs232_port tx_pin: TX rx_pin: RX baud_rate: 9600 # Define the data logger logger: - id: data_logger type: file filename: /data.log max_size: 1024KB level: DEBUG # Define the RS232 protocol rs232_protocol: - id: rs232_proto serial_port: rs232_port baud_rate: 9600 Example YAML Configuration esphome: name: rs232_data_logger esp32: board: esp32dev # ... (other configurations) logger: - id: data_logger type: file filename: /data.log max_size: 1024KB level: DEBUG rs232_protocol: - id: rs232_proto serial_port: rs232_port baud_rate: 9600 # Define the data logger automation automation: - alias: "Log RS232 Data" trigger: platform: rs232_protocol id: rs232_proto event: received_data action: - logger.log: level: DEBUG message: "Received RS232 Data: ${data}"