ioBroker-IoT-WindSensor

Important: This project based on my ioBroker IoT Framework V5

AndreasExner/ioBroker-IoT-Framework: ioBroker IoT Framework (based on NodeMCU ESP8266) (github.com)

Please refer to this documentation for the the basic setup and configuration.

Required Version: 5.3.2 (or higher)

Important: Serial output

This sketch needs the hardware serial interface for the communication with the wind direction sensor (RS485). That requires to change the serial output for debug and runtime information (Serial.print) to serial1. The attached version of the framework includes the changes already.

Description

Introduction

This sketch reads the wind speed and direction from devices similar to these (no affiliate links!):

Broco Garten Signalausgang Aluminiumlegierung Windrichtung Sensor Windfahne: AmazonSmile: Küche & Haushalt

Rosilesi Windgeschwindigkeitssensor - Impulssignalausgang Aluminiumlegierter Windgeschwindigkeitssensor Anemometer: AmazonSmile: Garten

Both are sold from different sellers and under different names as well. Since the wind speed sensor offers an analog output the wind direction sensor uses the RS486 interface.

De noising

The raw data will be send to the ioborker, because de nosing can be a challenging part of the this project.

For the wind speed and direction, the value is measured with round about 1 Hz and written into an array. The array is submitted to iobroker on every interval. The maximum size of the array is limited by the maximum length of an URL (2000 characters) to 250. The recommended interval for a "real time" display should be between 30 and 60. On the iobroker side, the array must be processed do extract the required information (see processWindSensorData.js for details).

Important: the target datapoints are not part of the json files!

Testing / debugging

Often the remote device is mounted somewhere on a rooftop or another inconvenient place. That's where this tool comes in and offers you a simulation for your lab:

AndreasExner/RS485-UART-EchoTest: This sketch is useful for debugging and testing RS485/UART wirings. (github.com)

Wiring

Both sensors require 12-24V DC power. The RS485 shield is used to convert RS485 into TTL. The FT232 is used for serial1 (debug/info)

Voltage divider resistors: 330 ohm and 150 ohm, 1% or better, 1/4 watts

UART communication

It took me a lot of time to fiddle out all the challenges within the RS232/RS485 communication. Some findings are:

• Ground your STP cable shield on one end
• The conversation form RS232 to RS485 requires a good timing
• Pulling up the RE/DE pulls up RX of the ESP as well. This leads into zero frames / framing errors between the frames
• -> CRC check / trimming of zero frames is required
• -> The RX frame size must be known / defined

History

Version: F5_1.1 2020-12-14

• Major bugfix: sketch does not work with debug=false
• Major improvements and bugfixes for the UART communication: CRC check, remove zero bytes etc.
• changed wind speed data transfer (for de-noising)
• minor fixes and improvements

Version: F5_1.0 (release) 2020-12-06

Tested environment

• Software
  • Arduino IDE 1.8.13 (Windows)
  • EspSoftwareSerial 6.10.0 plerup/espsoftwareserial: Implementation of the Arduino software serial for ESP8266 (github.com)
• Hardware
  • NodeMCU Lolin V3 (ESP8266MOD 12-F)
  • NodeMCU D1 Mini (ESP8266MOD 12-F)
  • 5 V MAX485 / RS485 Modul TTL to RS-485 MCU

Prerequisites

• You need a running Arduino IDE and at least basic knowledge how it works.
• You also need a running ioBroker instance and a little more than basic knowledge on that stuff.
• You need a REST API in your ioBroker setup
• You need to secure the REST API (for example, expose the required data only and hide any confidential and secret stuff)
• You need a userdata section in your ioBroker objects
• You should know how to work with IoT devices and electronics
• You need to read this first: AndreasExner/ioBroker-IoT-Framework: ioBroker IoT Framework (based on NodeMCU ESP8266) (github.com)

Setup

• Create a folder in your Arduino library folder
• Copy the primary sketch (e.g. WindSensor.ino) and the extension file (AEX_iobroker_IoT_Framework.ino) into the folder
• Open the primary sketch (e.g. WindSensor.ino)
• Install required libraries into your Arduino IDE
• Create (import) the datapoints in iobroker
  • 0_userdata.0.IoT-Devices.07.json (generic device configuration and monitoring)
  • 0_userdata.0.IoT.WindSensor.json (specific device configuration and data, production)
  • 0_userdata.0.IoT-Dev.WindSensor.json (specific device configuration and data, development, optional)
• Set values for datapoints (see iobroker datapoints)

Configuration

Generic device section

// device settings - change settings to match your requirements

const char* ssid     = "<ssid>"; // Wifi SSID
const char* password = "<password>"; //Wifi password

String SensorID = "DEV"; //predefinded sensor ID, DEV by default to prevent overwriting productive data

int interval = 10;  // waiting time for the first masurement and fallback on error reading interval from iobroker

bool DevMode = true; //enable DEV mode on boot (do not change)
bool debug = true; //debug to serial monitor
bool led = true; //enable external status LED on boot
bool sensor_active = false; // dectivate sensor(s) on boot (do not change)

• Enter proper Wifi information
• The SensorID is part of the URL's and important for the the iobroker communications
• Interval defines the delay between two data transmissions / measurements. This value is used initially after boot. The interval dynamically updates from iobroker
• The DevMode switch prevents the device from sending data into your productive datapoints. It is enabled by default and can be overwritten dynamically from iobroker
• debug enables a more detailed serial output
• led enables the onboard led (status)
• The sensor_active switch disables the loading of hardware specific code on startup. This is very useful to test a sketch on the bread board without the connected hardware. It is disabled by default and gets dynamically enabled from the iobrocker during boot, as long as nothing else is configured.

Device base URL's

/*
 * build base URL's
 * Change IP/FQND and path to match your environment
 */

String baseURL_DEVICE_GET = "http://192.168.1.240:8087/getPlainValue/0_userdata.0.IoT-Devices." + SensorID + ".";
String baseURL_DEVICE_SET = "http://192.168.1.240:8087/set/0_userdata.0.IoT-Devices." + SensorID + ".";

The base url's, one for read and one to write data, are pointing to your iobroker datapoints in the devices section. The SensorID will be added to complete the path.

iobroker datapoints

Devices section

The default path for the devices root folder is: 0_userdata.0.IoT-Devices. When the path is changed, it has to be changed in the sketch as well.

It is mandatory to setup the following datapoints prior the first device boot:

• DevMode If true, the baseURL's for the IoT-Dev section are used to prevent overwriting your production data. Also see generic device section.

• LED Controls the status LED. Also see generic device section.

• SensorActive Controls the hardware sensors. Also see generic device section.

• SensorName Easy to understand name for the sensor. Not used in the code.

• baseURL_GET_DEV points to the IoT-Dev datapoints in iobroker (e.g. 0_userdata.0.IoT-Dev.DEV)

  • http://192.168.1.240:8087/getPlainValue/0_userdata.0.IoT-Dev.WindSensor.
    

• baseURL_SET_DEV points to the IoT-Dev datapoints in iobroker (e.g. 0_userdata.0.IoT-Dev.DEV)

  • http://192.168.1.240:8087/set/0_userdata.0.IoT-Dev.WindSensor.
    

• baseURL_GET_PROD points to the IoT datapoints in iobroker (e.g. 0_userdata.0.IoT.Weather)

  • http://192.168.1.240:8087/getPlainValue/0_userdata.0.IoT.WindSensor.
    

• baseURL_SET_PROD points to the IoT datapoints in iobroker (e.g. 0_userdata.0.IoT.Weather)

  • http://192.168.1.240:8087/set/0_userdata.0.IoT.WindSensor.
    

These datapoints are for output only:

• ErrorLog Last info/error message from the device

• MAC HW wifi mac address of the device

• RSSI Last wifi RSSI information from the device

• Reset Depricated

Specific device configuration and data

Depending on the DevMode, the device reads config and writes data into different datapoint sections:

• Development root folder: 0_userdata.0.IoT-Dev
• Production root folder: 0_userdata.0.IoT

It is recommended to keep the datapoints in both sections identical to avoid errors when changing the DevMode. The values can be different. Setup these datapoints before boot up the device:

• Interval [10] Defines the delay (in seconds) between two data transmissions
• A0_Step_Voltage The voltage per step of the A/D converter for the windspeed sensor. Due to the line resistance it might be necessary to adjust these values individually. A good point to start is 0.03 V.

These datapoints are for output only:

• WindDirectionArray Array of wind direction values
• WindSpeedArray Array of wind speed values
• SensorID Sensor device ID
• crcErrors CRC errors during the last interval
• rxTimeOuts RX timeouts (missed frames) during the last interval

Build datapoint URL's function

void build_urls() {

  URL_SID = baseURL_DATA_SET + "SensorID?value=" + SensorID;
  URL_INT = baseURL_DATA_GET + "Interval";

  URL_A0_Step_Voltage = baseURL_DATA_GET + "A0_Step_Voltage";
  URL_crcErrors = baseURL_DATA_SET + "crcErrors?value=";
  URL_rxTimeOuts = baseURL_DATA_SET + "rxTimeOuts?value=";
  URL_WindDirectionArray = baseURL_DATA_SET + "WindDirectionArray?value=";
  URL_WindSpeedArray = baseURL_DATA_SET + "WindSpeedArray?value=";
}

These url's are pointing to the iobroker datapoints, defined in the json files and can be changed if required.

How it works

Boot phase / setup

• Connect Wifi
• Get Wifi State
• Get the dynamic configuration from iobroker (generic devices section)
• Build specific device URL's (based on the dynamic configuration)
• Send devices IP address
• Send device ID
• Send information about the last restart / reset
• Run's setup for active sensors

Loop

Every n-th tick, defined by the Interval, the following sequence will proceed:

• Loop (1 Hz)
  • Get data of all sensors
  • Serial output all sensor data
  • Interval reached
    • Get Wifi State (try reconnect first, then reset if not connected)
    • Send devices IP address
    • Get the dynamic configuration from iobroker (generic devices section)
    • Build specific device URL's (based on the dynamic configuration)
    • Send data to iobroker
    • Get configuration data (A0_Step_Voltage) for wind sensor from iobroker
    • Run setup for inactive sensors (if activated now)
    • Get the new interval (specific device section)
  • LED Blink

Appendix