add compensation temperature and humidity for SGP41

examples/ONE/ONE.ino

@@ -744,7 +744,7 @@ void setup() {
   /** Show boot display */
   Serial.println("Firmware Version: " + ag.getVersion());
   displayShowText("AirGradient ONE", "FW Version: ", ag.getVersion());
-  
+
   boardInit();
   delay(DISPLAY_DELAY_SHOW_CONTENT_MS);
 
@@ -2288,6 +2288,11 @@ static void tempHumUpdate(void) {
 
     Serial.printf("Temperature in C: %0.2f\r\n", temp);
     Serial.printf("Relative Humidity: %d\r\n", hum);
+
+    // Update compensation temperature and humidity for SGP41
+    if (hasSensorSGP) {
+      ag.sgp41.setCompensationTemperatureHumidity(temp, hum);
+    }
   } else {
     Serial.println("SHT read failed");
   }

examples/Open_Air/Open_Air.ino

@@ -1204,6 +1204,25 @@ static void pmUpdate(void) {
       pm2hum = 0;
     }
   }
+
+  if (hasSensorSGP) {
+    float temp;
+    float hum;
+    if (pmsResult_1 && pmsResult_2) {
+      temp = (temp_1 + temp_2) / 2.0f;
+      hum = (hum_1 + hum_2) / 2.0f;
+    } else {
+      if (pmsResult_1) {
+        temp = temp_1;
+        hum = hum_1;
+      }
+      if (pmsResult_2) {
+        temp = temp_2;
+        hum = hum_2;
+      }
+    }
+    ag.sgp41.setCompensationTemperatureHumidity(temp, hum);
+  }
 }
 
 static void co2Update(void) {

src/Sgp41/Sgp41.cpp

@@ -253,7 +253,20 @@ int Sgp41::getTvocRaw(void) { return tvocRaw; }
 
 /**
  * @brief Get NOX raw value
- * 
- * @return int 
+ *
+ * @return int
  */
 int Sgp41::getNoxRaw(void) { return noxRaw; }
+
+/**
+ * @brief Set compasation temperature and humidity to calculate TVOC and NOx
+ * index
+ *
+ * @param temp Temperature
+ * @param hum Humidity
+ */
+void Sgp41::setCompensationTemperatureHumidity(float temp, float hum) {
+  defaultT = static_cast<uint16_t>((temp + 45) * 65535 / 175);
+  defaultRh = static_cast<uint16_t>(hum * 65535 / 100);
+  AgLog("Update: defaultT: %d, defaultRh: %d", defaultT, defaultRh);
+}

src/Sgp41/Sgp41.h

@@ -25,6 +25,7 @@ public:
   int getNoxIndex(void);
   int getTvocRaw(void);
   int getNoxRaw(void);
+  void setCompensationTemperatureHumidity(float temp, float hum);
 
 private:
   bool onConditioning = true;