Min/Max values are taken after FIRST_MIN_MAX millisencods due to measurement failures

of the DHT22 at start.

WLAN_Thermometer.ino

@@ -30,6 +30,7 @@
 #define WIFI_CONNECT_TIMEOUT  30
 #define CFG_PORTAL_TIMEOUT    90
 #define DHTTYPE               DHT22
+#define FIRST_MIN_MAX         300000  // = 5 min
 
 LiquidCrystal_I2C lcd(LCD_I2C_ADDR, LCD_COL, LCD_ROW);
 looper sched;
@@ -195,30 +196,36 @@ void loop()
               client.print(temp[ACT]);
               client.println(" &deg;C</h2>\n");
               client.print("<h2 style=\"color:green;\">Minimum: ");
-              client.print(temp[MIN]);
+              if (millis() > FIRST_MIN_MAX)
+                client.print(temp[MIN]);
               client.println(" &deg;C</h2>\n");
               client.print("<h2 style=\"color:green;\">Maximum: ");
-              client.print(temp[MAX]);
+              if (millis() > FIRST_MIN_MAX)
+                client.print(temp[MAX]);
               client.println(" &deg;C</h2>\n");
               client.println("<h1 style=\"color:blue;\">Luftfeuchtigkeit</h1>\n");
               client.print("<h2 style=\"color:blue;\">Aktuell: ");
               client.print(hum[ACT]);
               client.println(" %</h2>\n");
               client.print("<h2 style=\"color:blue;\">Minimum: ");
-              client.print(hum[MIN]);
+              if (millis() > FIRST_MIN_MAX)
+                client.print(hum[MIN]);
               client.println(" %</h2>\n");
               client.print("<h2 style=\"color:blue;\">Maximum: ");
-              client.print(hum[MAX]);
+              if (millis() > FIRST_MIN_MAX)
+                client.print(hum[MAX]);
               client.println(" %</h2>\n");
               client.println("<h1 style=\"color:gray;\">Gef&uuml;hlte Temperatur</h1>\n");
               client.print("<h2 style=\"color:gray;\">Aktuell: ");
               client.print(heat[ACT]);
               client.println(" &deg;C</h2>\n");
               client.print("<h2 style=\"color:gray;\">Minimum: ");
-              client.print(heat[MIN]);
+              if (millis() > FIRST_MIN_MAX)
+                client.print(heat[MIN]);
               client.println(" &deg;C</h2>\n");
               client.print("<h2 style=\"color:gray;\">Maximum: ");
-              client.print(heat[MAX]);
+              if (millis() > FIRST_MIN_MAX)
+                client.print(heat[MAX]);
               client.println(" &deg;C</h2>\n");
 
               DateTimeParts p = DateTime.getParts();
@@ -341,9 +348,11 @@ void show_temperature(void)
   lcd.print("C");
   lcd.setCursor(0, 2);
   lcd.print("Min: ");
-  lcd.print(temp[MIN], 1);
+  if (millis() > FIRST_MIN_MAX)
+    lcd.print(temp[MIN], 1);
   lcd.print("  Max: ");
-  lcd.print(temp[MAX], 1);
+  if (millis() > FIRST_MIN_MAX)
+    lcd.print(temp[MAX], 1);
   lcd.setCursor(0, 3);
   lcd.print("LF:  ");
   lcd.print(hum[ACT], 1);
@@ -392,20 +401,24 @@ bool is_wintertime(time_t t)
 void get_sensor_data(void)
 {
   temp[ACT] = constrain(dht.readTemperature(), -40.0, 80.0);
-  if (temp[ACT] < temp[MIN])
-    temp[MIN] = temp[ACT];
-  if (temp[ACT] > temp[MAX])
-    temp[MAX] = temp[ACT];
-
   hum[ACT] = constrain(dht.readHumidity(), 0.0, 100.0);
-  if (hum[ACT] < hum[MIN])
-    hum[MIN] = hum[ACT];
-  if (hum[ACT] > hum[MAX])
-    hum[MAX] = hum[ACT];
-
   heat[ACT] = constrain(dht.computeHeatIndex(temp[ACT], hum[ACT], false), -40.0, 80.0);
-  if (heat[ACT] < heat[MIN])
-    heat[MIN] = heat[ACT];
-  if (heat[ACT] > heat[MAX])
-    heat[MAX] = heat[ACT];
+
+  if (millis() > FIRST_MIN_MAX)
+  {
+    if (temp[ACT] < temp[MIN])
+      temp[MIN] = temp[ACT];
+    if (temp[ACT] > temp[MAX])
+      temp[MAX] = temp[ACT];
+
+    if (hum[ACT] < hum[MIN])
+      hum[MIN] = hum[ACT];
+    if (hum[ACT] > hum[MAX])
+      hum[MAX] = hum[ACT];
+
+    if (heat[ACT] < heat[MIN])
+      heat[MIN] = heat[ACT];
+    if (heat[ACT] > heat[MAX])
+      heat[MAX] = heat[ACT];
+  }
 }