well I hope this fixes the build

Software/Software.ino

@@ -22,7 +22,7 @@
 #endif
 
 Preferences settings;  // Store user settings
-
+const char* version_number = "5.2.0";   // The current software version, shown on webserver
 // Interval settings
 int intervalUpdateValues = 4800;  // Interval at which to update inverter values / Modbus registers
 const int interval10 = 10;        // Interval for 10ms tasks
@@ -130,7 +130,9 @@ void setup() {
   init_webserver();
 #endif
 
+#ifdef EVENTLOGGING
   init_events();
+#endif
 
   init_CAN();
 

Software/USER_SETTINGS.cpp

@@ -36,5 +36,5 @@ const char* ssid = "REPLACE_WITH_YOUR_SSID";          // Maximum of 63 character
 const char* password = "REPLACE_WITH_YOUR_PASSWORD";  // Minimum of 8 characters;
 const char* ssidAP = "Battery Emulator";              // Maximum of 63 characters;
 const char* passwordAP = "123456789";  // Minimum of 8 characters; set to NULL if you want the access point to be open
-const char* versionNumber = "5.0.1";   // The current software version, shown on webserver
+const uint8_t wifi_channel = 0;         // set to 0 for automatic channel selection
 #endif

Software/USER_SETTINGS.h

@@ -75,4 +75,6 @@ extern volatile float CHARGER_END_A;
 extern bool charger_HV_enabled;
 extern bool charger_aux12V_enabled;
 
+extern const uint8_t wifi_channel;
+
 #endif

Software/src/devboard/mqtt/mqtt.cpp

@@ -70,7 +70,7 @@ static void publish_cell_voltages(void) {
                "\"unit_of_measurement\": \"V\","
                "\"value_template\": \"{{ value_json.cell_voltages[%d] }}\""
                "}",
-               i + 1, versionNumber, i + 1, i + 1, i);
+               i + 1, version_number, i + 1, i + 1, i);
       // End each discovery topic with cell number and '/config'
       String cell_topic = topic + String(i + 1) + "/config";
       mqtt_publish_retain(cell_topic.c_str());
@@ -154,7 +154,7 @@ static void publish_common_info(void) {
               "\"enabled_by_default\": true,"
               "\"state_class\": \"measurement\""
               "}",
-              config.name, state_topic, config.object_id, config.object_id, versionNumber, config.value_template, config.unit, config.device_class);
+              config.name, state_topic, config.object_id, config.object_id, version_number, config.value_template, config.unit, config.device_class);
       mqtt_publish_retain(config.topic);
     }
   } else {

Software/src/devboard/mqtt/mqtt.h

@@ -39,6 +39,8 @@
 
 #define MQTT_MSG_BUFFER_SIZE (1024)
 
+extern const char* version_number;            // The current software version, used for mqtt
+
 extern uint16_t SOC;
 extern uint16_t StateOfHealth;
 extern uint16_t temperature_min;    //C+1,  Goes thru convert2unsignedint16 function (15.0C = 150, -15.0C =  65385)

Software/src/devboard/utils/events.h

@@ -3,8 +3,8 @@
 
 #ifndef UNIT_TEST
 #include <Arduino.h>
-extern unsigned long time_seconds;
-extern uint32_t previous_millis;
+extern unsigned long previous_millis;
+extern uint32_t time_seconds;
 #endif
 
 #include <stdint.h>

Software/src/devboard/webserver/webserver.cpp

@@ -60,7 +60,7 @@ void init_webserver() {
   } else {
     WiFi.mode(WIFI_STA);  // Only Router connection
   }
-  init_WiFi_STA(ssid, password, channel);
+  init_WiFi_STA(ssid, password, wifi_channel);
 
   // Route for root / web page
   server.on("/", HTTP_GET,
@@ -301,7 +301,7 @@ void wifi_monitor() {
     if (status != WL_CONNECTED && status != WL_IDLE_STATUS) {
       Serial.println(getConnectResultString(status));
       if(wifi_state == INIT) { //we haven't been connected yet, try the init logic
-        init_WiFi_STA(ssid, password, channel);
+        init_WiFi_STA(ssid, password, wifi_channel);
       } else { //we were connected before, try the reconnect logic
         if (currentMillis - last_wifi_attempt_time > wifi_reconnect_interval) {
           last_wifi_attempt_time = currentMillis;
@@ -324,11 +324,11 @@ void wifi_monitor() {
   }
 }
 
-void init_WiFi_STA(const char* ssid, const char* password, const uint8_t channel) {
+void init_WiFi_STA(const char* ssid, const char* password, const uint8_t wifi_channel) {
   // Connect to Wi-Fi network with SSID and password
   Serial.print("Connecting to ");
   Serial.println(ssid);
-  WiFi.begin(ssid, password, channel);
+  WiFi.begin(ssid, password, wifi_channel);
   WiFi.setAutoReconnect(true);  // Enable auto reconnect
   wl_status_t result = static_cast<wl_status_t>(WiFi.waitForConnectResult(INIT_WIFI_CONNECT_TIMEOUT));
 }
@@ -354,7 +354,7 @@ String processor(const String& var) {
     content += "<div style='background-color: #303E47; padding: 10px; margin-bottom: 10px;border-radius: 50px'>";
 
     // Show version number
-    content += "<h4>Software version: " + String(versionNumber) + "</h4>";
+    content += "<h4>Software version: " + String(version_number) + "</h4>";
 
     // Display LED color
     content += "<h4>LED color: ";

Software/src/devboard/webserver/webserver.h

@@ -17,6 +17,7 @@
 #include "../mqtt/mqtt.h"
 #endif
 
+extern const char* version_number;            // The current software version, shown on webserver
 extern uint16_t SOC;                         //SOC%, 0-100.00 (0-10000)
 extern uint16_t StateOfHealth;               //SOH%, 0-100.00 (0-10000)
 extern uint16_t battery_voltage;             //V+1,  0-500.0 (0-5000)
@@ -40,10 +41,9 @@ extern EVENTS_STRUCT_TYPE entries[EVENT_NOF_EVENTS];
 
 extern const char* ssid;
 extern const char* password;
-extern const uint8_t channel;
+extern const uint8_t wifi_channel;
 extern const char* ssidAP;
 extern const char* passwordAP;
-extern const char* versionNumber;
 
 // Common charger parameters
 extern float charger_stat_HVcur;