/* Macrocell environmental sensor project EnviSens * * This firmware provides features to use the NodeMCU ESP12 unit as an environmental sensor broker. * It currently collects all the sensor information via I2C from a connected ATMEGA. * * (C) 2019 Macrocell - Environmental sensing solutions * proudly presented by Macrocell - FPGA Innovators */ #include #include #include #include "DHT.h" #include "configuration.h" #define TOPIC_BASE "sensor/" sensor_id "/" #define TOPIC_TEMP TOPIC_BASE "temperature" #define TOPIC_HMID TOPIC_BASE "humidity" #define TOPIC_HEAT TOPIC_BASE "heat_index" #define TOPIC_AIRQ TOPIC_BASE "air_gas" #define DIFF_TEMP 0.3 // sensor has only 0.5°C accuracy, triggering on less is ludicrous #define DIFF_HMID 2.5 // humidity doesn't change that much anyways #define DIFF_HEAT 0.2 // this one's actually quite active #define DIFF_AIRQ 3 // this one hardly changes float hmid = 0; // humidity float hmid_r = 0; // humidity float temp = 0; // temperature float temp_r = 0; // temperature float heat = 0; // heat index float heat_r = 0; // heat index float airq = 0; // air quality / gas float airq_r = 0; // air quality / gas char data[8]; char sensor_name[5]; float sensor_value; WiFiClient espClient; PubSubClient client(espClient); void setup() { Serial.begin(SERIAL_BAUDRATE); pinMode(LED_BUILTIN, OUTPUT); digitalWrite(LED_BUILTIN, LOW); setup_wifi(); client.setServer(mqtt_server, mqtt_port); Wire.begin(); // join i2c bus as master } void setup_wifi() { delay(10); // Connect to a WiFi network Serial.println(); Serial.print("Connecting to "); Serial.println(wifi_ssid); WiFi.begin(wifi_ssid, wifi_password); WiFi.mode(WIFI_STA); // blink LED fast until WiFi is connected while (WiFi.status() != WL_CONNECTED) { delay(200); digitalWrite(LED_BUILTIN, HIGH); Serial.print("."); delay(200); digitalWrite(LED_BUILTIN, LOW); } // WiFi connected Serial.println(""); Serial.println("WiFi connected"); Serial.println("IP address: "); Serial.println(WiFi.localIP()); } void reconnect() { // Loop until reconnected while (!client.connected()) { Serial.print("Attempting MQTT connection..."); // Attempt to connect if (client.connect(mqtt_client, mqtt_user, mqtt_password)) { Serial.println("connected"); } else { Serial.print("failed, rc="); Serial.print(client.state()); Serial.println(" try again in 5 seconds"); digitalWrite(LED_BUILTIN, HIGH); // Wait 5 seconds before retrying delay(4000); digitalWrite(LED_BUILTIN, LOW); delay(1000); } } } bool checkVariation(float newValue, float prevValue, float maxDiff) { return !isnan(newValue) && (newValue < prevValue - maxDiff || newValue > prevValue + maxDiff); } bool checkPlausibility(float newValue, float prevValue, float maxDiff) { return (newValue < prevValue + (maxDiff * 10) || newValue > prevValue - (maxDiff * 10)); } long lastMsg = 0; long lastSent = 0; bool published = false; bool forcePublish = false; bool publish (String desc, char *topic, float val, float &lastVal, float diff, bool force){ bool retval = false; if (checkVariation(val, lastVal, diff) or force) { lastVal = val; Serial.println("New " + desc + ": " + String(val).c_str()); if (checkPlausibility(val, lastVal, diff) or force) { Serial.println("Value published"); client.publish(topic, String(val).c_str(), true); retval = true; } else { Serial.print("** ERROR: Value out of bounds, not published. Last value :"); Serial.println(String(lastVal).c_str()); } } else { Serial.println("Not enough variation for a publication"); } return retval; } void loop() { if (!client.connected()) { reconnect(); } client.loop(); digitalWrite(LED_BUILTIN, HIGH); long now = millis(); if (now - lastMsg > OPERATION_PERIOD / 2) { if (OPERATION_BLINK_EN) {digitalWrite(LED_BUILTIN, LOW);} } if (now - lastMsg > OPERATION_PERIOD) { lastMsg = now; if (OPERATION_BLINK_EN) {digitalWrite(LED_BUILTIN, HIGH);} Wire.requestFrom(8, 8); // request 6 bytes from slave device #8 int i = 0; while(Wire.available()) { // slave may send less than requested char c = Wire.read(); // receive a byte as character data[i] = byte(c); i = i + 1; } union sensor_tag {byte sensor_b[4]; float sensor_float;} sensor_union; //DRPS = Drum Revs per Second sensor_name[0] = char(data[0]); sensor_name[1] = char(data[1]); sensor_name[2] = char(data[2]); sensor_name[3] = char(data[3]); sensor_name[4] = '\0'; sensor_union.sensor_b[0] = data[4]; sensor_union.sensor_b[1] = data[5]; sensor_union.sensor_b[2] = data[6]; sensor_union.sensor_b[3] = data[7]; sensor_value = sensor_union.sensor_float; Serial.print("Received sensor reading: "); Serial.print(sensor_name); Serial.print(" - "); Serial.println(sensor_value); if (strcmp(sensor_name, "hmid") == 0){ hmid = sensor_value; } else if (strcmp(sensor_name, "temp") == 0){ temp = sensor_value; } else if (strcmp(sensor_name, "heat") == 0){ heat = sensor_value; } else if (strcmp(sensor_name, "airq") == 0){ airq = sensor_value; } else{ Serial.println("ERR: Sensor could not be identified"); } published = false; if (lastSent > FORCE_PERIOD) { Serial.println(F("Forcing a publish of all values")); forcePublish = true; lastSent = 0; } published += publish("temperature", TOPIC_TEMP, temp, temp_r, DIFF_TEMP, forcePublish); published += publish("humidity", TOPIC_HMID, hmid, hmid_r, DIFF_HMID, forcePublish); published += publish("heat index", TOPIC_HEAT, heat, heat_r, DIFF_HEAT, forcePublish); published += publish("air quality", TOPIC_AIRQ, airq, airq_r, DIFF_AIRQ, forcePublish); if (published == false) { lastSent = lastSent + 1; } else { lastSent = 0; } forcePublish = false; } }