CatM1: allow retry if connection fails

src/CatM1ConnectionHandler.cpp

@@ -37,12 +37,15 @@ CatM1ConnectionHandler::CatM1ConnectionHandler(
 : ConnectionHandler{keep_alive, NetworkAdapter::CATM1}
 {
   _settings.type = NetworkAdapter::CATM1;
+  // To keep the backward compatibility, the user can call enableCheckInternetAvailability(false) for disabling the check
+  _check_internet_availability = true;
   strncpy(_settings.catm1.pin, pin, sizeof(_settings.catm1.pin)-1);
   strncpy(_settings.catm1.apn, apn, sizeof(_settings.catm1.apn)-1);
   strncpy(_settings.catm1.login, login, sizeof(_settings.catm1.login)-1);
   strncpy(_settings.catm1.pass, pass, sizeof(_settings.catm1.pass)-1);
   _settings.catm1.rat  = static_cast<uint8_t>(rat);
   _settings.catm1.band = band;
+  _reset = false;
 }
 
 /******************************************************************************
@@ -51,7 +54,10 @@ CatM1ConnectionHandler::CatM1ConnectionHandler(
 
 unsigned long CatM1ConnectionHandler::getTime()
 {
-  return GSM.getTime();
+  /* It is not safe to call GSM.getTime() since we don't know if modem internal
+   * RTC is in sync with current time.
+   */
+  return 0;
 }
 
 /******************************************************************************
@@ -61,6 +67,7 @@ unsigned long CatM1ConnectionHandler::getTime()
 NetworkConnectionState CatM1ConnectionHandler::update_handleInit()
 {
 #if defined (ARDUINO_EDGE_CONTROL)
+  /* Power on module */
   pinMode(ON_MKR2, OUTPUT);
   digitalWrite(ON_MKR2, HIGH);
 #endif
@@ -71,31 +78,36 @@ NetworkConnectionState CatM1ConnectionHandler::update_handleInit()
     _settings.catm1.login,
     _settings.catm1.pass,
     static_cast<RadioAccessTechnologyType>(_settings.catm1.rat) ,
-    _settings.catm1.band))
+    _settings.catm1.band,
+    _reset))
   {
     Debug.print(DBG_ERROR, F("The board was not able to register to the network..."));
-    return NetworkConnectionState::ERROR;
+    _reset = true;
+    return NetworkConnectionState::DISCONNECTED;
   }
+  _reset = false;
   return NetworkConnectionState::CONNECTING;
 }
 
 NetworkConnectionState CatM1ConnectionHandler::update_handleConnecting()
 {
   if (!GSM.isConnected())
   {
-    return NetworkConnectionState::INIT;
+    Debug.print(DBG_ERROR, F("GSM connection not alive... disconnecting"));
+    return NetworkConnectionState::DISCONNECTED;
   }
 
   if(!_check_internet_availability){
     return NetworkConnectionState::CONNECTED;
   }
 
-  int ping_result = GSM.ping("time.arduino.cc");
+  Debug.print(DBG_INFO, F("Sending PING to outer space..."));
+  int const ping_result = GSM.ping("time.arduino.cc");
   Debug.print(DBG_INFO, F("GSM.ping(): %d"), ping_result);
   if (ping_result < 0)
   {
     Debug.print(DBG_ERROR, F("Internet check failed"));
-    Debug.print(DBG_INFO, F("Retrying in  \"%d\" milliseconds"), CHECK_INTERVAL_TABLE[static_cast<unsigned int>(NetworkConnectionState::CONNECTING)]);
+    Debug.print(DBG_INFO, F("Retrying in  \"%d\" milliseconds"), 2 * CHECK_INTERVAL_TABLE[static_cast<unsigned int>(NetworkConnectionState::CONNECTING)]);
     return NetworkConnectionState::CONNECTING;
   }
   else
@@ -110,6 +122,7 @@ NetworkConnectionState CatM1ConnectionHandler::update_handleConnected()
   int const is_gsm_access_alive = GSM.isConnected();
   if (is_gsm_access_alive != 1)
   {
+    Debug.print(DBG_ERROR, F("GSM connection not alive... disconnecting"));
     return NetworkConnectionState::DISCONNECTED;
   }
   return NetworkConnectionState::CONNECTED;
@@ -123,6 +136,7 @@ NetworkConnectionState CatM1ConnectionHandler::update_handleDisconnecting()
 
 NetworkConnectionState CatM1ConnectionHandler::update_handleDisconnected()
 {
+  GSM.end();
   if (_keep_alive)
   {
     return NetworkConnectionState::INIT;

src/CatM1ConnectionHandler.h

@@ -60,6 +60,8 @@ class CatM1ConnectionHandler : public ConnectionHandler
 
   private:
 
+    bool _reset;
+
     GSMUDP _gsm_udp;
     GSMClient _gsm_client;
 };