/* ESP32 based Weather Station with a WiFi Server to provide sensor data for Prometheus to scrape . Borrowed information from: Jeff Geerling - https://github.com/geerlingguy/airgradient-prometheus - https://www.jeffgeerling.com/blog/2021/airgradient-diy-air-quality-monitor-co2-pm25 AirGradient - https://www.airgradient.com/diyshop/#!/DIY-AQ-Kit-1/p/447361353/category=128812596 ESP32 example "SimpleWiFiServer" https://randomnerdtutorials.com/esp32-websocket-server-arduino/ Arduino BME280 library One day, in a future version, I plan to learn how to make all of the windvane code into a library. This will simplify the code overall. Written by Trevor Hone, 29 Mar 2022. Releasable to the general public. */ #include #include #include #include #include /* I found this on this forum thread https://forum.arduino.cc/t/fill-whole-array-with-the-same-value/66313/7 and I intend to use it to reset arrays. I plan on using an array to track position values instead of 128 separate variables. An alternative would be to use memset(yourArray,0,sizeof(yourArray)); */ // Config ---------------------------------------------------------------------- // WiFi and IP connection info. const char* ssid = "Your WIFI SSID here"; const char* password = "Your WIFI password here"; const int port = 9921; const char* deviceId = "Weather_station"; BME280I2C::Settings settings( BME280::OSR_X1, BME280::OSR_X1, BME280::OSR_X1, BME280::Mode_Forced, BME280::StandbyTime_1000ms, BME280::Filter_Off, BME280::SpiEnable_False, BME280I2C::I2CAddr_0x77 // I2C address. I2C specific. ); BME280I2C bme(settings); // Constants for calculating voltage and Windspeed. ESP32 assigns a 12 bit number (0-4095) for voltages from 0-3.3V const float adc_constant = (3.3/4095); // For calculating wind position and direction byte windPosition_raw = 0b00000000; const byte encoder_key[128] = {0b01111111, 0b00111111, 0b00111110, 0b00111010, 0b00111000, 0b10111000, 0b10011000, \ 0b00011000, 0b00001000, 0b01001000, 0b01001001, 0b01001101, 0b01001111, 0b00001111, 0b00101111, 0b10101111, 0b10111111, \ 0b10011111, 0b00011111, 0b00011101, 0b00011100, 0b01011100, 0b01001100, 0b00001100, 0b00000100, 0b00100100, 0b10100100, \ 0b10100110, 0b10100111, 0b10000111, 0b10010111, 0b11010111, 0b11011111, 0b11001111, 0b10001111, 0b10001110, 0b00001110, \ 0b00101110, 0b00100110, 0b00000110, 0b00000010, 0b00010010, 0b01010010, 0b01010011, 0b11010011, 0b11000011, 0b11001011, \ 0b11101011, 0b11101111, 0b11100111, 0b11000111, 0b01000111, 0b00000111, 0b00010111, 0b00010011, 0b00000011, 0b00000001, \ 0b00001001, 0b00101001, 0b10101001, 0b11101001, 0b11100001, 0b11100101, 0b11110101, 0b11110111, 0b11110011, 0b11100011, \ 0b10100011, 0b10000011, 0b10001011, 0b10001001, 0b10000001, 0b10000000, 0b10000100, 0b10010100, 0b11010100, 0b11110100, \ 0b11110000, 0b11110010, 0b11111010, 0b11111011, 0b11111001, 0b11110001, 0b11010001, 0b11000001, 0b11000101, 0b11000100, \ 0b11000000, 0b01000000, 0b01000010, 0b01001010, 0b01101010, 0b01111010, 0b01111000, 0b01111001, 0b01111101, 0b11111101, \ 0b11111100, 0b11111000, 0b11101000, 0b11100000, 0b11100010, 0b01100010, 0b01100000, 0b00100000, 0b00100001, 0b00100101, \ 0b00110101, 0b00111101, 0b00111100, 0b10111100, 0b10111110, 0b11111110, 0b01111110, 0b01111100, 0b01110100, 0b01110000, \ 0b01110001, 0b00110001, 0b00110000, 0b00010000, 0b10010000, 0b10010010, 0b10011010, 0b10011110, 0b00011110, 0b01011110, \ 0b01011111 }; int position_count[128]; const float positionToDegree = 2.8515625; // this is the number that results from 365/128 and is used to convert position to degrees // Config End ------------------------------------------------------------------ // Start the webserver and make gloabally available WebServer server(port); void setup() { analogSetAttenuation(ADC_11db); // Sets the input attenuation for ALL ADC inputs, default is ADC_11db, range is ADC_0db, ADC_2_5db, ADC_6db, ADC_11db Serial.begin(9600); String hostname = deviceId; pinMode(5, OUTPUT); // set the LED pin mode delay(10); // start communication with BME280 sensor Wire.begin(); while(!bme.begin()) { Serial.println("Could not find BME280 sensor!"); delay(1000); } // Setting pins to read windvane encoder outputs pinMode(12, INPUT); pinMode(13, INPUT); pinMode(14, INPUT); pinMode(25, INPUT); pinMode(26, INPUT); pinMode(27, INPUT); pinMode(32, INPUT); pinMode(33, INPUT); // Connecting to a WiFi network Serial.println(); Serial.print("Connecting to "); Serial.println(ssid); WiFi.config(INADDR_NONE, INADDR_NONE, INADDR_NONE, INADDR_NONE); WiFi.setHostname(hostname.c_str()); //define hostname WiFi.begin(ssid, password); while (WiFi.status() != WL_CONNECTED) { delay(500); Serial.print("."); } Serial.println(""); Serial.println("WiFi connected."); Serial.println("Signal Strength: " + WiFi.RSSI()); Serial.println("IP address: "); Serial.println(WiFi.localIP()); Serial.print("MAC address: "); Serial.println(WiFi.macAddress()); Serial.print("Hostname: "); Serial.println(WiFi.getHostname()); server.on("/", HandleRoot); server.on("/metrics", HandleRoot); server.onNotFound(HandleNotFound); server.begin(); Serial.println("HTTP server started at ip " + WiFi.localIP().toString() + ":" + String(port)); } void loop() { /* * This section is used to sample the wind direction. * My prometheus server will query the device every 30sec which is where I reset the array. * If you don't have a similar setup, add a periodic memset(position_count,0,sizeof(position_count)); * in order to keep the data clean and consistent. */ int current_position = -1; bitWrite(windPosition_raw, 7, digitalRead(13)); bitWrite(windPosition_raw, 6, digitalRead(12)); bitWrite(windPosition_raw, 5, digitalRead(14)); bitWrite(windPosition_raw, 4, digitalRead(27)); bitWrite(windPosition_raw, 3, digitalRead(26)); bitWrite(windPosition_raw, 2, digitalRead(25)); bitWrite(windPosition_raw, 1, digitalRead(33)); bitWrite(windPosition_raw, 0, digitalRead(32)); current_position = findPosition(windPosition_raw); if (current_position != -1) { position_count[current_position]++; } // looking for a call to the webserver server.handleClient(); // delay for stability delay(20); } void HandleRoot() { server.send(200, "text/plain", GenerateMetrics() ); //server.send(200, "text/plain", "hello"); } void HandleNotFound() { String message = "File Not Found\n\n"; message += "URI: "; message += server.uri(); message += "\nMethod: "; message += (server.method() == HTTP_GET) ? "GET" : "POST"; message += "\nArguments: "; message += server.args(); message += "\n"; for (uint i = 0; i < server.args(); i++) { message += " " + server.argName(i) + ": " + server.arg(i) + "\n"; } server.send(404, "text/html", message); } String GenerateMetrics() { // setup bme sensor calls (borrowed from the BME280 I2C Test.ino) float temp(NAN), hum(NAN), pres(NAN); BME280::TempUnit tempUnit(BME280::TempUnit_Celsius); BME280::PresUnit presUnit(BME280::PresUnit_Pa); bme.read(pres, temp, hum, tempUnit, presUnit); // Calculations for C to F and "standard" barometric pressure with temp changes float temp_f = (temp * 9/5) + 32; //convert the temp to farenheight for display float baro = 1013.25*exp(-((0.02896*9.807)/(8.3143*(temp+273.15))*1292.96)); // Setting up the string formatting for prometheus String message = ""; String idString = "{id=\"" + String(deviceId) + "\",mac=\"" + WiFi.macAddress().c_str() + "\"} "; /* Calculating voltage & windspeed and adding to the message * Sensor output parameters * Voltage Min = 0.4 * Voltage Max = 2 * Wind Speed Min = 0 * Wind Speed Max = 32.4 */ analogSetAttenuation(ADC_11db); //setting attenuation to be able to handle the top voltage https://randomnerdtutorials.com/esp32-adc-analog-read-arduino-ide/ float sensorValue = analogReadMilliVolts(39); // get the ADC reading in millivolts //float anemometerVoltage = sensorValue * adc_constant; //ESP32 12 bit reading to voltage float anemometerVoltage = sensorValue/1000; float wind_speed = (anemometerVoltage - 0.418) * (32.4 - 0) / (2 - 0.4); // (voltage_reading - voltage_min) * (windspeed_max - windspeed_min) / (voltage_max - voltage_min) + windspeed_min float speed_mph = ((wind_speed *3600)/1609.344); /* //For troubleshooting Serial.println(analogReadMilliVolts(39)); Serial.println(anemometerVoltage); Serial.println(wind_speed); Serial.println(speed_mph); */ message += "# HELP wind_mph Anemometer windspeed\n"; message += "wind_mph"; message += idString; message += String(speed_mph); message += "\n"; /* * Adding the wind direction to the message */ //For troubleshooting //Serial.println(findPosition(windPosition_raw)); int windMode = windPosition_mode(); memset(position_count,0,sizeof(position_count)); float windMode_degrees = windMode * positionToDegree; // String cardinal_direction = cardinal(windMode_degrees); message += "# HELP wind_degrees 8-bit DIY windvane direction in degrees\n"; message += "wind_degrees"; message += idString; message += String(windMode_degrees); message += "\n"; /* //It appears that Prometheus does not allow for string values at this time (LAME!) // Having the cardinal direction separate for now. message += "# HELP 8-bit DIY windvane cardinal direction\n"; message += "wind_direction_cardinal"; message += idString; message += cardinal_direction; message += "\n"; */ /* * Adding the BME280 data to the message stream for prometheus * Temp converted into F from C * Pressure in hPa * Relative Humidity */ message += "# HELP BME280 Temperature\n"; message += "temp_f"; message += idString; message += String(temp_f); message += "\n"; message += "# HELP BME280 Pressure in hPa\n"; message += "pressure_hpa"; message += idString; message += String(pres/100); message += "\n"; message += "# HELP BME280 Relative Humidity percent\n"; message += "relative_hum"; message += idString; message += String(hum); message += "\n"; message += "# HELP Calculated 'average' barometric pressure based on tempurature and 4242ft (1292.96m) at home\n"; message += "baro"; message += idString; message += String(baro); message += "\n"; return message; } int findPosition(byte desiredValue){ int val_position; for (int i=0; i < 128; i++){ if (desiredValue == encoder_key[i]){ val_position = i; break; } } return val_position; } int windPosition_mode(){ int max_v = -1; int max_i = -1; for ( int i = 0; i < 128; i++ ) { if ( position_count[i] > max_v ) { max_v = position_count[i]; max_i = i; } } return max_i; } /* //This takes the degrees from the windvane and returns a string value of the cardinal direction String cardinal (float deg){ String cardinal_val; if(deg == 0){ cardinal_val = "N"; } if(deg > 348.75 || deg <= 11.25){ cardinal_val = "N"; } else if ((deg > 11.25) && (deg <= 33.75)){ cardinal_val = "NNE"; } else if ((deg > 33.75) && (deg <= 56.25)){ cardinal_val = "NE"; } else if ((deg > 56.25) && (deg <= 78.75)){ cardinal_val = "ENE"; } else if ((deg > 78.75) && (deg <= 101.25)){ cardinal_val = "E"; } else if ((deg > 101.25) && (deg <= 123.75)){ cardinal_val = "ESE"; } else if ((deg > 123.75) && (deg <= 146.25)){ cardinal_val = "SE"; } else if ((deg > 146.25) && (deg <= 168.75)){ cardinal_val = "SSE"; } else if ((deg > 168.75) && (deg <= 191.25)){ cardinal_val = "S"; } else if ((deg > 191.25) && (deg <= 213.75)){ cardinal_val = "SSW"; } else if ((deg > 213.75) && (deg <= 236.25)){ cardinal_val = "SW"; } else if ((deg > 236.25) && (deg <= 258.75)){ cardinal_val = "WSW"; } else if ((deg > 258.75) && (deg <= 281.25)){ cardinal_val = "W"; } else if ((deg > 281.25) && (deg <= 303.75)){ cardinal_val = "WNW"; } else if ((deg > 303.75) && (deg <= 326.25)){ cardinal_val = "NW"; } else if ((deg > 325.25) && (deg <= 348.75)){ cardinal_val = "NNW"; } return cardinal_val; } */ /* * this is unused for now int arrayMax(int myArray[], int sizeOfArray){ int max_v = INT_MIN; int max_i = -1; for ( int i = 0; i < sizeOfArray; i++ ) { if ( myArray[i] > max_v ) { max_v = myArray[i]; max_i = i; } } return max_i; } */