firmware wip - swap PINfan and PINpump, according to PCB

set analogWriteFreq to 220Hz. This was so far the sweetspot for
Fan PWM control in combination with a 47µF electrolyt capacitor.

If I had a PWM pin free, i would use PWM functionality of pc fans
but all pins are in use. So I went with putting a capacitor to the
output and regulate the fan speed this way.

Arduino/CanGrow/CanGrow.ino

@@ -707,8 +707,10 @@ bool loadEEPROM() {
    * 
    * -- afterwards added, need to sort --
    * 
-   * 213 UseLEDrelais 
+   * 213 PINled_PWM 
    * 214 TemperatureSensor_Type 
+   * 215 UseFANrelais
+   * 216 PINfan_PWM
    * 
    */
    
@@ -768,7 +770,13 @@ bool loadEEPROM() {
       // I forgot to add TemperatureSensor_Type to EEPROM and noticed it
       // quite late in the process of programming. So this value residents
       // in 214 and not directly after UseLEDrelais
+      EEPROM.get(213, PINled_PWM);
+      // size is 1 byte
       EEPROM.get(214, TemperatureSensor_Type);
+      // size is 1 byte
+      EEPROM.get(215, UseFANrelais);
+      // size is 1 byte
+      EEPROM.get(216, PINfan_PWM);
     }
     // TODO auth does not work atm 
     // EEPROM.get(160, WebUiUsername);
@@ -798,14 +806,6 @@ bool loadEEPROM() {
       // size is 1 byte
       EEPROM.get(212, DayOfGrow);
       
-      // to ensure PINled_PWM always set to 255 when UseLEDrelais is true
-      // we set it here again, does not matter whats stored.
-      // size is 1 byte
-      if(UseLEDrelais == true) {
-        PINled_PWM = 255;
-      } else {
-        EEPROM.get(213, PINled_PWM);
-      }
     }
 
     
@@ -837,6 +837,8 @@ bool loadEEPROM() {
     Serial.println(ntpOffset);
     Serial.print("UseLEDrelais: ");
     Serial.println(UseLEDrelais);
+    Serial.print("UseFANrelais: ");
+    Serial.println(UseFANrelais);
 
     Serial.println("---- Grow values ----");
     Serial.print("GrowName: ");
@@ -859,6 +861,8 @@ bool loadEEPROM() {
     Serial.println(DayOfGrow);
     Serial.print("PINled_PWM: ");
     Serial.println(PINled_PWM);
+    Serial.print("PINfan_PWM: ");
+    Serial.println(PINfan_PWM);
     
     
   } else {
@@ -972,6 +976,9 @@ void setup() {
   digitalWrite(PINled, LOW);
   digitalWrite(PINpump, LOW);
 
+  // set frequency lower to avoid annoying noises
+  analogWriteFreq(220);
+
   // Start Serial
   Serial.begin(115200);
 
@@ -1438,8 +1445,14 @@ void WEBroot() {
     body += "<option disabled value='' selected hidden>---</option>\n";
     body += "<option value='1'>On</option>\n";
     body += "<option value='0'>Off</option>\n";
-    
     body += "</select><br>\n";
+    
+    if(UseFANrelais == false) {
+      body += "Speed FAN: <input type='range' id='PINfan_PWM' name='PINfan_PWM' min='1' max='255' value='";
+      body += PINfan_PWM;
+      body += "'/><br>\n";
+    }
+    
     body += "<input type='submit' value='Save'>\n";
     body += "</form>";
     
@@ -1569,6 +1582,13 @@ void WEBsystemSettings() {
     body += "<option value='0'" + returnStrSelected(UseLEDrelais, 0) + ">No</option>\n";
     body += "</select><br>\n";
 
+    // UseFANrelais bool
+    body += "Use relais for FAN: <select id='UseFANrelais' name='UseFANrelais' required>\n";
+    if(configured == false){body += "<option disabled value='' selected hidden>---</option>\n";}
+    body += "<option value='1'" + returnStrSelected(UseFANrelais, 1) + ">Yes</option>\n";
+    body += "<option value='0'" + returnStrSelected(UseFANrelais, 0) + ">No</option>\n";
+    body += "</select><br>\n";
+    
     // TODO ugly. can this done be better? 
     // PumpOnTime int
     body += "Pump on time: <input type='number' name='PumpOnTime' min='0' max='255' value='";
@@ -1687,6 +1707,12 @@ void WEBgrowSettings() {
       body += "'/><br>\n";
     }
     
+    if(UseFANrelais == false) {
+      body += "Speed FAN: <input type='range' id='PINfan_PWM' name='PINfan_PWM' min='1' max='255' value='";
+      body += PINfan_PWM;
+      body += "'/><br>\n";
+    }
+    
     body += "<input type='submit' value='Save'>\n";
     body += "</form>\n"; 
     body += FPSTR(JSconvertDateToEpoch);
@@ -1713,6 +1739,14 @@ void POSTgrowSettings() {
     PINled_PWM = webserver.arg("PINled_PWM").toInt();
   }
   
+  if(UseFANrelais == true) {
+    // if a relais is used to turn on grow light, we force PWM to max val
+    PINfan_PWM = 255;
+  } else {
+    // otherwise just do PWM
+    PINfan_PWM = webserver.arg("PINfan_PWM").toInt();
+  }
+  
   String GrowName_tmp = webserver.arg("GrowName");
   GrowName_tmp.toCharArray(GrowName, 32);
   
@@ -1743,6 +1777,9 @@ void POSTgrowSettings() {
   EEPROM.put(211, SunriseMinute);
   // size is 1 byte
   EEPROM.put(213, PINled_PWM);
+  // size is 1 byte
+  EEPROM.put(216, PINfan_PWM);
+  
   
   EEPROM.commit();
   
@@ -1771,6 +1808,8 @@ void POSTgrowSettings() {
   Serial.println(SunriseMinute);
   Serial.print("PINled_PWM: ");
   Serial.println(PINled_PWM);
+  Serial.print("PINfan_PWM: ");
+  Serial.println(PINfan_PWM);
   
   webserver.sendHeader("Location", String("/growSettings?success"), true);
   webserver.send(302, "text/plain", "growSettings/save: success!\n");  
@@ -1785,6 +1824,7 @@ void POSTsystemSettings() {
   PumpOnTime = webserver.arg("PumpOnTime").toInt();
   UseFan = webserver.arg("UseFan").toInt();
   UseLEDrelais = webserver.arg("UseLEDrelais").toInt();
+  UseFANrelais = webserver.arg("UseFANrelais").toInt();
   TemperatureSensor_Type = webserver.arg("TemperatureSensor_Type").toInt();
   
   configured = true;
@@ -1807,6 +1847,8 @@ void POSTsystemSettings() {
   EEPROM.put(169, UseLEDrelais);
   // size is 1 byte
   EEPROM.put(214, TemperatureSensor_Type);
+  // size is 1 byte
+  EEPROM.put(215, UseFANrelais);
   
   // write data to EEPROM
   EEPROM.commit();
@@ -1828,6 +1870,13 @@ void POSTsystemSettings() {
     Serial.println("UseLEDrelais is 1, forcing PINled_PWM to max to prevent relais damage");
   }
   
+  if(UseFANrelais == true) {
+    PINfan_PWM = 255;
+    EEPROM.put(215, PINfan_PWM);
+    EEPROM.commit();
+    Serial.println("UseFANrelais is 1, forcing PINfan_PWM to max to prevent relais damage");
+  }
+    
   Serial.print("configured: ");
   Serial.println(configured);
   Serial.print("UseFan: ");
@@ -1844,6 +1893,8 @@ void POSTsystemSettings() {
   Serial.println(ntpOffset);
   Serial.print("UseLEDrelais: ");
   Serial.println(UseLEDrelais);
+  Serial.print("UseFANrelais: ");
+  Serial.println(UseFANrelais);
   Serial.print("TemperatureSensor_Type: ");
   Serial.println(TemperatureSensor_Type);
   
@@ -1922,6 +1973,7 @@ void POSTwifiSettings() {
 void POSTswitchMOSFET() {
   byte MosfetState = webserver.arg("state").toInt();
   byte MosfetNr = webserver.arg("output").toInt();
+  byte PINfan_PWM = webserver.arg("PINfan_PWM").toInt();
   
   Serial.println(":: GETswitchMOSFET ::");
   Serial.print("MosfetState: ");
@@ -1935,7 +1987,11 @@ void POSTswitchMOSFET() {
     switch(MosfetNr) {
       case 1:
         if(MosfetState == 1) {
+          if(UseLEDrelais == true) {
+            digitalWrite(PINled, MosfetState);
+          } else {
             analogWrite(PINled, PINled_PWM);
+          }
         } else {
           digitalWrite(PINled, MosfetState);
         }
@@ -1944,7 +2000,15 @@ void POSTswitchMOSFET() {
         digitalWrite(PINpump, MosfetState);
         break;
       case 3:
+        if(MosfetState == 1) {
+          if(UseFANrelais == true) {
             digitalWrite(PINfan, MosfetState);
+          } else {
+            analogWrite(PINfan, PINfan_PWM);
+          }
+        } else {
+          digitalWrite(PINfan, MosfetState);
+        }
         break;
       default:
         webserver.send(400, "text/plain", "not valid\n");
@@ -1996,7 +2060,7 @@ void APIgetSensors() {
  * - PWM for fan control
  * - avoid using javascript to set the GrowName in the Menu and the time
  *   as well
- * - 
+ * - rework UseLEDrelais usage
  * 
  *    
 */