started implementing PM sensor

firmware/CMakeListsPrivate.txt

@@ -21,7 +21,7 @@ SET(CMAKE_C_STANDARD 99)
 set(CMAKE_CXX_STANDARD 11)
 
 if (CMAKE_BUILD_TYPE MATCHES "esp32dev")
-    add_definitions(-DPLATFORMIO=50204)
+    add_definitions(-DPLATFORMIO=50205)
     add_definitions(-DARDUINO_ESP32_DEV)
     add_definitions(-DESP32)
     add_definitions(-DESP_PLATFORM)
@@ -36,6 +36,8 @@ if (CMAKE_BUILD_TYPE MATCHES "esp32dev")
     include_directories("${CMAKE_CURRENT_LIST_DIR}/include")
     include_directories("${CMAKE_CURRENT_LIST_DIR}/src")
     include_directories("$ENV{HOME}/.platformio/packages/framework-arduinoespressif32/libraries/BLE/src")
+    include_directories("${CMAKE_CURRENT_LIST_DIR}/.pio/libdeps/esp32dev/esp_sds011/src")
+    include_directories("${CMAKE_CURRENT_LIST_DIR}/.pio/libdeps/esp32dev/EspSoftwareSerial/src")
     include_directories("${CMAKE_CURRENT_LIST_DIR}/.pio/libdeps/esp32dev/Adafruit BMP280 Library")
     include_directories("${CMAKE_CURRENT_LIST_DIR}/.pio/libdeps/esp32dev/Adafruit BusIO")
     include_directories("$ENV{HOME}/.platformio/packages/framework-arduinoespressif32/libraries/SPI/src")

firmware/platformio.ini

@@ -13,3 +13,4 @@ platform = espressif32
 board = esp32dev
 framework = arduino
 lib_deps = adafruit/Adafruit BMP280 Library@^2.6.1
+    dok-net/esp_sds011@^1.0.0

firmware/src/main.cpp

@@ -1,6 +1,7 @@
 #include <Arduino.h>
 #include <sensors/BmpSensor.h>
 #include <ble/BluetoothServer.h>
+#include <sensors/PmSensor.h>
 
 #define SLEEP_TIME 1
 #define BAUD_RATE 112500
@@ -9,6 +10,7 @@
 
 
 Sensor *bmpSensor;
+Sensor *pmSensor;
 BluetoothServer *server;
 bool makeDiscoverable = false;
 
@@ -18,11 +20,16 @@ void IRAM_ATTR startBleServerAdvertising() {
 }
 
 void setup() {
+    //initialize a Serial Connection
     Serial.begin(BAUD_RATE);
+    //setup the internal LED
     pinMode(INTERNAL_LED_PIN, OUTPUT);
 
+    //create sensor objects
     bmpSensor = new BmpSensor();
+    pmSensor = new PmSensor();
 
+    //setup & start Bluetooth server
     server = new BluetoothServer();
     server->startServer();
 
@@ -39,8 +46,22 @@ void loop() {
         makeDiscoverable = false;
     }
 
+    //setup PM sensor measurement TODO: This blocks for 120 seconds and needs to be executed asynchronously
+    //((PmSensor *) pmSensor)->startAsyncSampling();
+
+    //obtain measurement from BMP280 Sensor
     sensor_data_t sample = ((BmpSensor *) bmpSensor)->sampleLowEnergy();
     server->setPressure(sample.pressure);
     server->setTemperature(sample.temperature);
+    //Obtain measurement from PM Sensor
+    sensor_data_t pmSample = pmSensor->sample();
+
+    //Print measured data
+    Serial.printf("Pressure: %f hPa | Temperature: %f °C | PM10: %f ppm| PM2.5: %f ppm\n",
+                  sample.pressure,
+                  sample.temperature,
+                  pmSample.pm10,
+                  pmSample.pm25);
+    //wait for one measurement cycle
     delay(SLEEP_TIME * 1000);
 }

firmware/src/sensors/BmpSensor.cpp

@@ -69,7 +69,9 @@ sensor_data_t BmpSensor::sample() {
     return sensor_data_t
             {
                     temp_event.temperature,
-                    pressure_event.pressure
+                    pressure_event.pressure,
+                    0.0,
+                    0.0
             };
 }
 

firmware/src/sensors/BmpSensor.h

@@ -14,6 +14,7 @@ public:
     BmpSensor();
 
     sensor_data_t sample() override;
+
     sensor_data_t sampleLowEnergy();
 
     void enableStandbyMode() override;

firmware/src/sensors/PmSensor.cpp

@@ -0,0 +1,95 @@
+#include "PmSensor.h"
+#include <SoftwareSerial.h>
+#include <Sds011.h>
+
+#define SDS_PIN_RX 18
+#define SDS_PIN_TX 19
+#define SENSOR_BAUD_RATE 9600
+#define SLEEP_TIME 90
+#define MEASURE_TIME 30
+
+#ifdef ESP32
+HardwareSerial &serialSDS(Serial2);
+Sds011Async<HardwareSerial> sds011(serialSDS);
+#else
+SoftwareSerial serialSDS;
+Sds011Async< SoftwareSerial > sds011(serialSDS);
+#endif
+
+
+PmSensor::PmSensor() {
+    this->PmSensor::sensor_setup();
+}
+
+void PmSensor::startAsyncSampling() {
+
+    this->enableStandbyMode();
+    PmSensor::sensorWait(SLEEP_TIME);
+
+    this->wakeUp();
+    sds011.perform_work();
+
+    if (!sds011.query_data_auto_async(pm_tablesize, pm25_table, pm10_table)) {
+        Serial.println("measurement capture start failed");
+    }
+
+    PmSensor::sensorWait(MEASURE_TIME);
+}
+
+/**
+ * Put the sensor to standby mode
+ */
+void PmSensor::enableStandbyMode() {
+    if (sds011.set_sleep(true)) { this->state = SensorState::ASLEEP; }
+}
+
+/**
+ * Activate the sensor
+ */
+void PmSensor::wakeUp() {
+    if (sds011.set_sleep(false)) { this->state = SensorState::AWAKE; }
+}
+
+/**
+ * Method to set up and initialize the sensor
+ */
+void PmSensor::sensor_setup() {
+#ifdef ESP32
+    serialSDS.begin(SENSOR_BAUD_RATE, SERIAL_8N1, SDS_PIN_RX, SDS_PIN_TX);
+    delay(100);
+#else
+    serialSDS.begin(SENSOR_BAUD_RATE, SWSERIAL_8N1, SDS_PIN_RX, SDS_PIN_TX, false, 192);
+#endif
+
+    //put the sensor into standby mode initially
+    this->PmSensor::enableStandbyMode();
+    Serial.println("SDS011 sensor initialized to standby mode.");
+
+    //attach a callback on what to do when data sampling is complete
+    sds011.on_query_data_auto_completed([this](int n) {
+        int pm25;
+        int pm10;
+        if (sds011.filter_data(n, pm25_table, pm10_table, pm25, pm10) &&
+            !isnan(pm10) && !isnan(pm25)) {
+            //set the right values
+            this->latestPM10 = float(pm10) / 10;
+            this->latestPM25 = float(pm25) / 10;
+        }
+    });
+}
+
+/**
+ * Method to wait for some time and perform the appropriate task
+ * @param time the time to wait for in seconds
+ */
+void PmSensor::sensorWait(int time) {
+    uint32_t deadline = millis() + time * 1000;
+    while (static_cast<int32_t>(deadline - millis()) > 0) {
+        delay(1000);
+        sds011.perform_work();
+    }
+}
+
+sensor_data_t PmSensor::sample() {
+    return {0.0, 0.0, this->latestPM10, this->latestPM25};
+}

firmware/src/sensors/PmSensor.h

@@ -0,0 +1,35 @@
+#ifndef FIRMWARE_PMSENSOR_H
+#define FIRMWARE_PMSENSOR_H
+
+#include "Sensor.h"
+#include "sensor_data_t.h"
+
+class PmSensor : public Sensor {
+public:
+    static const int pm_tablesize = 20;
+    int pm25_table[pm_tablesize];
+    int pm10_table[pm_tablesize];
+
+    float latestPM10;
+    float latestPM25;
+
+    PmSensor();
+
+    sensor_data_t sample() override;
+
+    void startAsyncSampling();
+
+
+    void enableStandbyMode() override;
+
+    void wakeUp() override;
+
+protected:
+    void sensor_setup() override;
+
+private:
+    static void sensorWait(int time);
+};
+
+
+#endif //FIRMWARE_PMSENSOR_H

firmware/src/sensors/Sensor.h

@@ -1,5 +1,5 @@
-#ifndef NEW_CLIMTE_GO_SENSOR_H
-#define NEW_CLIMTE_GO_SENSOR_H
+#ifndef FIRMWARE_SENSOR_H
+#define FIRMWARE_SENSOR_H
 
 #include <sensors/sensor_data_t.h>
 

firmware/src/sensors/sensor_data_t.h

@@ -1,7 +1,5 @@
-#ifndef NEW_CLIMTE_GO_SENSOR_DATA_T_H
-#define NEW_CLIMTE_GO_SENSOR_DATA_T_H
-
-#include <types.h>
+#ifndef FIRMWARE_SENSOR_DATA_T_H
+#define FIRMWARE_SENSOR_DATA_T_H
 
 /**
  * This struct represents data read from any sensor.
@@ -11,6 +9,8 @@
 struct sensor_data_t {
     float temperature;
     float pressure;
+    float pm10;
+    float pm25;
 };
 
 #endif