outdoor_module.ino

#include <Wire.h>
#include <Arduino.h>
#include <NOxGasIndexAlgorithm.h>
#include <SensirionI2CSgp41.h>
#include <VOCGasIndexAlgorithm.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BME280.h>
#include <HardwareSerial.h>
//#include <TinyGPS++.h>

#include "PMS.h"

#define SEALEVELPRESSURE_HPA (1013.25)
#define RXD2 16 // To sensor TXD
#define TXD2 17 // To sensor RXD

SensirionI2CSgp41 sgp41;
Adafruit_BME280 bme;

VOCGasIndexAlgorithm voc_algorithm;
NOxGasIndexAlgorithm nox_algorithm;

// time in seconds needed for NOx conditioning
uint16_t conditioning_s = 10;
bool status;

String val1;
String val2;
String val3;

struct pms5003data {
  uint16_t framelen;
  uint16_t pm10_standard, pm25_standard, pm100_standard;
  uint16_t pm10_env, pm25_env, pm100_env;
  uint16_t particles_03um, particles_05um, particles_10um, particles_25um, particles_50um, particles_100um;
  uint16_t unused;
  uint16_t checksum;
};
 
struct pms5003data data;

void setup() {
    Serial.begin(115200);
    while (!Serial) {
        delay(100);
    }
    Serial1.begin(9600, SERIAL_8N1, RXD2, TXD2);
    
    Wire.begin(); 
    sgp41.begin(Wire);
    status = bme.begin(0x76);
    
    delay(1000);  // needed on some Arduino boards in order to have Serial ready

    int32_t index_offset;
    int32_t learning_time_offset_hours;
    int32_t learning_time_gain_hours;
    int32_t gating_max_duration_minutes;
    int32_t std_initial;
    int32_t gain_factor;
    voc_algorithm.get_tuning_parameters(
        index_offset, learning_time_offset_hours, learning_time_gain_hours,
        gating_max_duration_minutes, std_initial, gain_factor);

    Serial.println("\nVOC Gas Index Algorithm parameters");
    Serial.print("Index offset:\t");
    Serial.println(index_offset);
    Serial.print("Learing time offset hours:\t");
    Serial.println(learning_time_offset_hours);
    Serial.print("Learing time gain hours:\t");
    Serial.println(learning_time_gain_hours);
    Serial.print("Gating max duration minutes:\t");
    Serial.println(gating_max_duration_minutes);
    Serial.print("Std inital:\t");
    Serial.println(std_initial);
    Serial.print("Gain factor:\t");
    Serial.println(gain_factor);

    nox_algorithm.get_tuning_parameters(
        index_offset, learning_time_offset_hours, learning_time_gain_hours,
        gating_max_duration_minutes, std_initial, gain_factor);

    Serial.println("\nNOx Gas Index Algorithm parameters");
    Serial.print("Index offset:\t");
    Serial.println(index_offset);
    Serial.print("Learing time offset hours:\t");
    Serial.println(learning_time_offset_hours);
    Serial.print("Gating max duration minutes:\t");
    Serial.println(gating_max_duration_minutes);
    Serial.print("Gain factor:\t");
    Serial.println(gain_factor);
    Serial.println("");
}

void loop() {
    uint16_t error;
    float humidity = 0;     // %RH
    float temperature = 0;  // degreeC
    float pressure = 0;     //hPa
    float appaltitude = 0;  //m
    uint16_t srawVoc = 0;
    uint16_t srawNox = 0;
    uint16_t defaultCompenstaionRh = 0x8000;  // in ticks as defined by SGP41
    uint16_t defaultCompenstaionT = 0x6666;   // in ticks as defined by SGP41
    uint16_t compensationRh = 0;              // in ticks as defined by SGP41
    uint16_t compensationT = 0;               // in ticks as defined by SGP41

    // 1. Sleep: Measure every second (1Hz), as defined by the Gas Index
    // Algorithm
    //    prerequisite
    delay(1000);

    // 2. Measure temperature and humidity for SGP internal compensation
    //error = sht4x.measureHighPrecision(temperature, humidity);
    //if (error) {
    if (!status){
        //Serial.print("SHT4x - Error trying to execute measureHighPrecision(): ");
        Serial.print("BME280 - Error trying to execute begin");
        //errorToString(error, errorMessage, 256);
        //Serial.println(errorMessage);
        Serial.println("Fallback to use default values for humidity and "
                       "temperature compensation for SGP41");
        compensationRh = defaultCompenstaionRh;
        compensationT = defaultCompenstaionT;
    } else {
        humidity = bme.readHumidity();
        temperature = bme.readTemperature();
        pressure = (bme.readPressure()/100.0F);
        appaltitude = bme.readAltitude(SEALEVELPRESSURE_HPA);
        Serial.print("Temperature:");
        Serial.print(temperature);
        Serial.print("\t");
        Serial.print("Relative Humidity:");
        Serial.println(humidity);
        Serial.print("Pressure:");
        Serial.print(pressure);
        Serial.print("\t");
        Serial.print("Approx. Altitude:");
        Serial.println(appaltitude);
        // convert temperature and humidity to ticks as defined by SGP41
        // interface
        // NOTE: in case you read RH and T raw signals check out the
        // ticks specification in the datasheet, as they can be different for
        // different sensors
        compensationT = static_cast<uint16_t>((temperature + 45) * 65535 / 175);
        compensationRh = static_cast<uint16_t>(humidity * 65535 / 100);
    }

    // 3. Measure SGP4x signals
    if (conditioning_s > 0) {
        // During NOx conditioning (10s) SRAW NOx will remain 0
        error =
            sgp41.executeConditioning(compensationRh, compensationT, srawVoc);
        conditioning_s--;
    } else {
        error = sgp41.measureRawSignals(compensationRh, compensationT, srawVoc,
                                        srawNox);
    }

    // 4. Process raw signals by Gas Index Algorithm to get the VOC and NOx
    // index
    //    values
    if (error) {
        Serial.print("SGP41 - Error trying to execute measureRawSignals(): ");
        //errorToString(error, errorMessage, 256);
        //Serial.println(errorMessage);
    } else {
        int32_t voc_index = voc_algorithm.process(srawVoc);
        int32_t nox_index = nox_algorithm.process(srawNox);
        Serial.print("VOC Index: ");
        Serial.print(voc_index);
        Serial.print("\t");
        Serial.print("NOx Index: ");
        Serial.println(nox_index);
    }

  if (readPMSdata(&Serial1)) {
    // reading data was successful!
    Serial.println();
    Serial.println("---------------------------------------");
    Serial.println("Concentration Units (standard)");
    Serial.print("PM 1.0: "); Serial.print(data.pm10_standard);
    Serial.print("\t\tPM 2.5: "); Serial.print(data.pm25_standard);
    Serial.print("\t\tPM 10: "); Serial.println(data.pm100_standard);
    Serial.println("---------------------------------------");
    Serial.println("Concentration Units (environmental)");
    Serial.print("PM 1.0: "); Serial.print(data.pm10_env);
    Serial.print("\t\tPM 2.5: "); Serial.print(data.pm25_env);
    Serial.print("\t\tPM 10: "); Serial.println(data.pm100_env);
    Serial.println("---------------------------------------");
    Serial.print("Particles > 0.3um / 0.1L air:"); Serial.println(data.particles_03um);
    Serial.print("Particles > 0.5um / 0.1L air:"); Serial.println(data.particles_05um);
    Serial.print("Particles > 1.0um / 0.1L air:"); Serial.println(data.particles_10um);
    Serial.print("Particles > 2.5um / 0.1L air:"); Serial.println(data.particles_25um);
    Serial.print("Particles > 5.0um / 0.1L air:"); Serial.println(data.particles_50um);
    Serial.print("Particles > 10.0 um / 0.1L air:"); Serial.println(data.particles_100um);
    Serial.println("---------------------------------------");
  }
}

boolean readPMSdata(Stream *s) {
  if (! s->available()) {
    return false;
  }
 
  // Read a byte at a time until we get to the special '0x42' start-byte
  if (s->peek() != 0x42) {
    s->read();
    return false;
  }
 
  // Now read all 32 bytes
  if (s->available() < 32) {
    return false;
  }
 
  uint8_t buffer[32];
  uint16_t sum = 0;
  s->readBytes(buffer, 32);
 
  // get checksum ready
  for (uint8_t i = 0; i < 30; i++) {
    sum += buffer[i];
  }
 
  /* debugging
    for (uint8_t i=2; i<32; i++) {
    Serial.print("0x"); Serial.print(buffer[i], HEX); Serial.print(", ");
    }
    Serial.println();
  */
 
  // The data comes in endian'd, this solves it so it works on all platforms
  uint16_t buffer_u16[15];
  for (uint8_t i = 0; i < 15; i++) {
    buffer_u16[i] = buffer[2 + i * 2 + 1];
    buffer_u16[i] += (buffer[2 + i * 2] << 8);
  }
 
  // put it into a nice struct :)
  memcpy((void *)&data, (void *)buffer_u16, 30);
 
  if (sum != data.checksum) {
    Serial.println("Checksum failure");
    return false;
  }
  // success!
  return true;
}