LoRaWAN MAC layer implementation

Dependents:   LoRaWAN-demo-72_tjm LoRaWAN-demo-72_jlc LoRaWAN-demo-elmo frdm_LoRa_Connect_Woodstream_Demo_tjm ... more

LoRAWAN-lib is a port of the GitHub LoRaMac-node LoRaWAN MAC layer implementation.

This library depends on the SX1276Lib or SX1272Lib radio drivers depending on the used mbed component shield.

This library depends also on some cryptographic helper functions as well as helper functions for the timers management. These can be found on the example projects under the system directory.

The example projects are:

  1. LoRaWAN-demo-72
  2. LoRaWAN-demo-76
  3. LoRaWAN-demo-NAMote72

The LoRaWAN specification specifies different ISM bands operating parameters. These are all implemented under the LoRaMac-board.h file.

In order to select which band to use, please change line 24 of board.h file provided on the examples projects as follows:


EU868

board.h

#define USE_BAND_868


US915

board.h

#define USE_BAND_915


US915 - Hybrid

board.h

#define USE_BAND_915_HYBRID


CN780

board.h

#define USE_BAND_780


EU433

board.h

#define USE_BAND_433
Revision:
3:b9d87593a8ae
Parent:
2:14a5d6ad92d5
Child:
4:37c12dbc8dc7
diff -r 14a5d6ad92d5 -r b9d87593a8ae LoRaMac.cpp
--- a/LoRaMac.cpp	Tue Jan 05 16:41:54 2016 +0000
+++ b/LoRaMac.cpp	Mon Mar 14 09:09:54 2016 +0000
@@ -300,12 +300,6 @@
     LC1,
     LC2,
     LC3,
-    LC4,
-    LC5,
-    LC6,
-    LC7,
-    LC8,
-    LC9,
 };
 #elif defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID )
 /*!
@@ -447,6 +441,7 @@
     MAC_ACK_REQ       = 0x00000004,
     MAC_ACK_RETRY     = 0x00000008,
     MAC_TX_DELAYED    = 0x00000010,
+    MAC_TX_CONFIG     = 0x00000020,
 };
 
 /*!
@@ -562,6 +557,12 @@
 static void OnRadioTxDone( void );
 
 /*!
+ * \brief This function prepares the MAC to abort the execution of function
+ *        OnRadioRxDone in case of a reception error.
+ */
+static void PrepareRxDoneAbort( void );
+
+/*!
  * \brief Function to be executed on Radio Rx Done event
  */
 static void OnRadioRxDone( uint8_t *payload, uint16_t size, int16_t rssi, int8_t snr );
@@ -609,9 +610,13 @@
 /*!
  * \brief Searches and set the next random available channel
  *
- * \retval status  Function status [0: OK, 1: Unable to find a free channel]
+ * \param [OUT] Time to wait for the next transmission according to the duty
+ *              cycle.
+ *
+ * \retval status  Function status [1: OK, 0: Unable to find a channel on the
+ *                                  current datarate]
  */
-static TimerTime_t SetNextChannel( void );
+static bool SetNextChannel( TimerTime_t* time );
 
 /*!
  * \brief Sets the network to public or private. Updates the sync byte.
@@ -833,6 +838,28 @@
     }
 }
 
+static void PrepareRxDoneAbort( void )
+{
+    LoRaMacState &= ~MAC_TX_RUNNING;
+
+    if( NodeAckRequested )
+    {
+        OnAckTimeoutTimerEvent( );
+    }
+
+    if( ( RxSlot == 0 ) && ( LoRaMacDeviceClass == CLASS_C ) )
+    {
+        OnRxWindow2TimerEvent( );
+    }
+
+    LoRaMacFlags.Bits.McpsInd = 1;
+    LoRaMacFlags.Bits.MacDone = 1;
+
+    // Trig OnMacCheckTimerEvent call as soon as possible
+    TimerSetValue( &MacStateCheckTimer, 1000 );
+    TimerStart( &MacStateCheckTimer );
+}
+
 static void OnRadioRxDone( uint8_t *payload, uint16_t size, int16_t rssi, int8_t snr )
 {
     LoRaMacHeader_t macHdr;
@@ -941,11 +968,13 @@
                     ChannelParams_t param;
                     param.DrRange.Value = ( DR_5 << 4 ) | DR_0;
 
+                    LoRaMacState |= MAC_TX_CONFIG;
                     for( uint8_t i = 3, j = 0; i < ( 5 + 3 ); i++, j += 3 )
                     {
                         param.Frequency = ( ( uint32_t )LoRaMacRxPayload[13 + j] | ( ( uint32_t )LoRaMacRxPayload[14 + j] << 8 ) | ( ( uint32_t )LoRaMacRxPayload[15 + j] << 16 ) ) * 100;
                         LoRaMacChannelAdd( i, param );
                     }
+                    LoRaMacState &= ~MAC_TX_CONFIG;
                 }
 #endif
                 MlmeConfirm.Status = LORAMAC_EVENT_INFO_STATUS_OK;
@@ -960,8 +989,6 @@
         case FRAME_TYPE_DATA_CONFIRMED_DOWN:
         case FRAME_TYPE_DATA_UNCONFIRMED_DOWN:
             {
-                LoRaMacFlags.Bits.McpsInd = 1;
-
                 address = payload[pktHeaderLen++];
                 address |= ( (uint32_t)payload[pktHeaderLen++] << 8 );
                 address |= ( (uint32_t)payload[pktHeaderLen++] << 16 );
@@ -985,13 +1012,8 @@
                     if( multicast == 0 )
                     {
                         // We are not the destination of this frame.
-                        LoRaMacFlags.Bits.MacDone = 1;
                         McpsIndication.Status = LORAMAC_EVENT_INFO_STATUS_ADDRESS_FAIL;
-                        LoRaMacState &= ~MAC_TX_RUNNING;
-                        if( NodeAckRequested )
-                        {
-                            OnAckTimeoutTimerEvent( );
-                        }
+                        PrepareRxDoneAbort( );
                         return;
                     }
                 }
@@ -1003,12 +1025,6 @@
                     downLinkCounter = DownLinkCounter;
                 }
 
-                if( LoRaMacDeviceClass != CLASS_A )
-                {
-                    LoRaMacState |= MAC_RX;
-                    // Starts the MAC layer status check timer
-                    TimerStart( &MacStateCheckTimer );
-                }
                 fCtrl.Value = payload[pktHeaderLen++];
 
                 sequenceCounter = ( uint16_t )payload[pktHeaderLen++];
@@ -1066,14 +1082,9 @@
                         if( ( curMulticastParams->DownLinkCounter == downLinkCounter ) &&
                             ( curMulticastParams->DownLinkCounter != 0 ) )
                         {
-                            LoRaMacFlags.Bits.MacDone = 1;
                             McpsIndication.Status = LORAMAC_EVENT_INFO_STATUS_DOWNLINK_REPEATED;
                             McpsIndication.DownLinkCounter = downLinkCounter;
-                            LoRaMacState &= ~MAC_TX_RUNNING;
-                            if( NodeAckRequested == true )
-                            {
-                                OnAckTimeoutTimerEvent( );
-                            }
+                            PrepareRxDoneAbort( );
                             return;
                         }
                         curMulticastParams->DownLinkCounter = downLinkCounter;
@@ -1082,36 +1093,25 @@
                     {
                         if( macHdr.Bits.MType == FRAME_TYPE_DATA_CONFIRMED_DOWN )
                         {
+                            SrvAckRequested = true;
                             McpsIndication.McpsIndication = MCPS_CONFIRMED;
                         }
                         else
                         {
+                            SrvAckRequested = false;
                             McpsIndication.McpsIndication = MCPS_UNCONFIRMED;
                         }
                         if( ( DownLinkCounter == downLinkCounter ) &&
                             ( DownLinkCounter != 0 ) )
                         {
-                            LoRaMacFlags.Bits.MacDone = 1;
                             McpsIndication.Status = LORAMAC_EVENT_INFO_STATUS_DOWNLINK_REPEATED;
                             McpsIndication.DownLinkCounter = downLinkCounter;
-                            LoRaMacState &= ~MAC_TX_RUNNING;
-                            if( NodeAckRequested == true )
-                            {
-                                OnAckTimeoutTimerEvent( );
-                            }
+                            PrepareRxDoneAbort( );
                             return;
                         }
                         DownLinkCounter = downLinkCounter;
                     }
 
-                    if( macHdr.Bits.MType == FRAME_TYPE_DATA_CONFIRMED_DOWN )
-                    {
-                        SrvAckRequested = true;
-                    }
-                    else
-                    {
-                        SrvAckRequested = false;
-                    }
                     // Check if the frame is an acknowledgement
                     if( fCtrl.Bits.Ack == 1 )
                     {
@@ -1174,34 +1174,32 @@
                             McpsIndication.RxData = true;
                         }
                     }
+                    LoRaMacFlags.Bits.McpsInd = 1;
                 }
                 else
                 {
                     McpsIndication.Status = LORAMAC_EVENT_INFO_STATUS_MIC_FAIL;
-                    LoRaMacState &= ~MAC_TX_RUNNING;
-                    if( NodeAckRequested == true )
-                    {
-                        OnAckTimeoutTimerEvent( );
-                    }
+
+                    PrepareRxDoneAbort( );
+                    return;
                 }
             }
             break;
         case FRAME_TYPE_PROPRIETARY:
             {
-                LoRaMacFlags.Bits.McpsInd = 1;
-
                 memcpy1( LoRaMacRxPayload, &payload[pktHeaderLen], size );
 
                 McpsIndication.McpsIndication = MCPS_PROPRIETARY;
                 McpsIndication.Status = LORAMAC_EVENT_INFO_STATUS_OK;
                 McpsIndication.Buffer = LoRaMacRxPayload;
                 McpsIndication.BufferSize = size - pktHeaderLen;
+
+                LoRaMacFlags.Bits.McpsInd = 1;
                 break;
             }
         default:
-            LoRaMacFlags.Bits.McpsInd = 1;
             McpsIndication.Status = LORAMAC_EVENT_INFO_STATUS_ERROR;
-            LoRaMacState &= ~MAC_TX_RUNNING;
+            PrepareRxDoneAbort( );
             break;
     }
 
@@ -1209,8 +1207,11 @@
     {
         OnRxWindow2TimerEvent( );
     }
-
     LoRaMacFlags.Bits.MacDone = 1;
+
+    // Trig OnMacCheckTimerEvent call as soon as possible
+    TimerSetValue( &MacStateCheckTimer, 1000 );
+    TimerStart( &MacStateCheckTimer );
 }
 
 static void OnRadioTxTimeout( void )
@@ -1336,6 +1337,7 @@
             if( ( McpsConfirm.AckReceived == true ) || ( AckTimeoutRetriesCounter > AckTimeoutRetries ) )
             {
                 AckTimeoutRetry = false;
+                NodeAckRequested = false;
                 if( IsUpLinkCounterFixed == false )
                 {
                     UpLinkCounter++;
@@ -1387,6 +1389,7 @@
 #endif
                 LoRaMacState &= ~MAC_TX_RUNNING;
 
+                NodeAckRequested = false;
                 McpsConfirm.AckReceived = false;
                 McpsConfirm.NbRetries = AckTimeoutRetriesCounter;
                 if( IsUpLinkCounterFixed == false )
@@ -1420,6 +1423,7 @@
     else
     {
         // Operation not finished restart timer
+        TimerSetValue( &MacStateCheckTimer, MAC_STATE_CHECK_TIMEOUT );
         TimerStart( &MacStateCheckTimer );
     }
 
@@ -1546,9 +1550,10 @@
     }
 }
 
-static TimerTime_t SetNextChannel( void )
+static bool SetNextChannel( TimerTime_t* time )
 {
     uint8_t nbEnabledChannels = 0;
+    uint8_t delayTx = 0;
     uint8_t enabledChannels[LORA_MAX_NB_CHANNELS];
     TimerTime_t curTime = TimerGetCurrentTime( );
     TimerTime_t nextTxDelay = ( TimerTime_t )( -1 );
@@ -1556,11 +1561,28 @@
     memset1( enabledChannels, 0, LORA_MAX_NB_CHANNELS );
 
 #if defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID )
-    if( ( CountNbEnabled125kHzChannels( ChannelsMaskRemaining ) +
-        ( ChannelsMaskRemaining[4] & 0x00FF ) ) == 0 )
+    if( CountNbEnabled125kHzChannels( ChannelsMaskRemaining ) == 0 )
+    { // Restore default channels
+        memcpy1( ( uint8_t* ) ChannelsMaskRemaining, ( uint8_t* ) ChannelsMask, 8 );
+    }
+    if( ( ChannelsDatarate >= DR_4 ) && ( ( ChannelsMaskRemaining[4] & 0x00FF ) == 0 ) )
+    { // Make sure, that the channels are activated
+        ChannelsMaskRemaining[4] = ChannelsMask[4];
+    }
+#else
+    uint8_t chanCnt = 0;
+    for( uint8_t i = 0, k = 0; i < LORA_MAX_NB_CHANNELS; i += 16, k++ )
     {
-        memcpy1( ( uint8_t* ) ChannelsMaskRemaining, ( uint8_t* ) ChannelsMask,
-                 sizeof( ChannelsMask ) );
+        if( ChannelsMask[k] != 0 )
+        {
+            chanCnt++;
+            break;
+        }
+    }
+    if( chanCnt == 0 )
+    {
+        // Re-enable default channels, if no channel is enabled
+        ChannelsMask[0] = ChannelsMask[0] | ( LC( 1 ) + LC( 2 ) + LC( 3 ) );
     }
 #endif
 
@@ -1605,21 +1627,16 @@
                 {
                     if( Channels[i + j].Frequency == 0 )
                     { // Check if the channel is enabled
-#if defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID )
-                        DisableChannelInMask( i + j, ChannelsMaskRemaining );
-#endif
                         continue;
                     }
                     if( ( ( Channels[i + j].DrRange.Fields.Min <= ChannelsDatarate ) &&
                           ( ChannelsDatarate <= Channels[i + j].DrRange.Fields.Max ) ) == false )
                     { // Check if the current channel selection supports the given datarate
-#if defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID )
-                        DisableChannelInMask( i + j, ChannelsMaskRemaining );
-#endif
                         continue;
                     }
                     if( Bands[Channels[i + j].Band].TimeOff > 0 )
                     { // Check if the band is available for transmission
+                        delayTx++;
                         continue;
                     }
                     enabledChannels[nbEnabledChannels++] = i + j;
@@ -1629,6 +1646,7 @@
     }
     else
     {
+        delayTx++;
         nextTxDelay = AggregatedTimeOff - ( curTime - AggregatedLastTxDoneTime );
     }
 
@@ -1636,14 +1654,25 @@
     {
         Channel = enabledChannels[randr( 0, nbEnabledChannels - 1 )];
 #if defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID )
-        DisableChannelInMask( Channel, ChannelsMaskRemaining );
+        if( Channel < ( LORA_MAX_NB_CHANNELS - 8 ) )
+        {
+            DisableChannelInMask( Channel, ChannelsMaskRemaining );
+        }
 #endif
-        return 0;
+        *time = 0;
+        return true;
     }
     else
     {
-        // Protect the function of returning the initialization value of nextTxDelay
-        return ( nextTxDelay == ( TimerTime_t )( -1 ) ) ? 0 : nextTxDelay;
+        if( delayTx > 0 )
+        {
+            // Delay transmission due to AggregatedTimeOff or to a band time off
+            *time = nextTxDelay;
+            return true;
+        }
+        // Datarate not supported by any channel
+        *time = 0;
+        return false;
     }
 }
 
@@ -1813,38 +1842,10 @@
         {
             AdrAckCounter = 0;
             adrAckReq = false;
-
-            if( updateChannelMask == true )
-            {
-#if defined( USE_BAND_433 ) || defined( USE_BAND_780 ) || defined( USE_BAND_868 )
-                // Re-enable default channels LC1, LC2, LC3
-                ChannelsMask[0] = ChannelsMask[0] | ( LC( 1 ) + LC( 2 ) + LC( 3 ) );
-#elif defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID )
-#if defined( USE_BAND_915 )
-                // Re-enable default channels
-                ChannelsMask[0] = 0xFFFF;
-                ChannelsMask[1] = 0xFFFF;
-                ChannelsMask[2] = 0xFFFF;
-                ChannelsMask[3] = 0xFFFF;
-                ChannelsMask[4] = 0x00FF;
-                ChannelsMask[5] = 0x0000;
-#else // defined( USE_BAND_915_HYBRID )
-                // Re-enable default channels
-                ChannelsMask[0] = 0x00FF;
-                ChannelsMask[1] = 0x0000;
-                ChannelsMask[2] = 0x0000;
-                ChannelsMask[3] = 0x0000;
-                ChannelsMask[4] = 0x0001;
-                ChannelsMask[5] = 0x0000;
-#endif
-#else
-#error "Please define a frequency band in the compiler options."
-#endif
-            }
         }
         else
         {
-            if( AdrAckCounter > ADR_ACK_LIMIT )
+            if( AdrAckCounter >= ADR_ACK_LIMIT )
             {
                 adrAckReq = true;
             }
@@ -1852,26 +1853,60 @@
             {
                 adrAckReq = false;
             }
-            if( AdrAckCounter > ( ADR_ACK_LIMIT + ADR_ACK_DELAY ) )
+            if( AdrAckCounter >= ( ADR_ACK_LIMIT + ADR_ACK_DELAY ) )
             {
-                AdrAckCounter = 0;
+                if( ( ( AdrAckCounter - ADR_ACK_DELAY ) % ADR_ACK_LIMIT ) == 0 )
+                {
 #if defined( USE_BAND_433 ) || defined( USE_BAND_780 ) || defined( USE_BAND_868 )
-                if( datarate > LORAMAC_MIN_DATARATE )
-                {
-                    datarate--;
-                }
+                    if( datarate > LORAMAC_MIN_DATARATE )
+                    {
+                        datarate--;
+                    }
+                    if( datarate == LORAMAC_MIN_DATARATE )
+                    {
+                        if( updateChannelMask == true )
+                        {
+
+                            // Re-enable default channels LC1, LC2, LC3
+                            ChannelsMask[0] = ChannelsMask[0] | ( LC( 1 ) + LC( 2 ) + LC( 3 ) );
+                        }
+                    }
 #elif defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID )
-                if( ( datarate > LORAMAC_MIN_DATARATE ) && ( datarate == DR_8 ) )
-                {
-                    datarate = DR_4;
-                }
-                else if( datarate > LORAMAC_MIN_DATARATE )
-                {
-                    datarate--;
-                }
+                    if( ( datarate > LORAMAC_MIN_DATARATE ) && ( datarate == DR_8 ) )
+                    {
+                        datarate = DR_4;
+                    }
+                    else if( datarate > LORAMAC_MIN_DATARATE )
+                    {
+                        datarate--;
+                    }
+                    if( datarate == LORAMAC_MIN_DATARATE )
+                    {
+                        if( updateChannelMask == true )
+                        {
+#if defined( USE_BAND_915 )
+                            // Re-enable default channels
+                            ChannelsMask[0] = 0xFFFF;
+                            ChannelsMask[1] = 0xFFFF;
+                            ChannelsMask[2] = 0xFFFF;
+                            ChannelsMask[3] = 0xFFFF;
+                            ChannelsMask[4] = 0x00FF;
+                            ChannelsMask[5] = 0x0000;
+#else // defined( USE_BAND_915_HYBRID )
+                            // Re-enable default channels
+                            ChannelsMask[0] = 0x00FF;
+                            ChannelsMask[1] = 0x0000;
+                            ChannelsMask[2] = 0x0000;
+                            ChannelsMask[3] = 0x0000;
+                            ChannelsMask[4] = 0x0001;
+                            ChannelsMask[5] = 0x0000;
+#endif
+                        }
+                    }
 #else
 #error "Please define a frequency band in the compiler options."
 #endif
+                }
             }
         }
     }
@@ -2193,8 +2228,10 @@
             case SRV_MAC_NEW_CHANNEL_REQ:
                 {
                     uint8_t status = 0x03;
+
 #if ( defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID ) )
-                    status &= 0xFE; // Channel frequency KO
+                    status &= 0xFC; // Channel frequency and datarate KO
+                    macIndex += 5;
 #else
                     int8_t channelIndex = 0;
                     ChannelParams_t chParam;
@@ -2206,21 +2243,52 @@
                     chParam.Frequency *= 100;
                     chParam.DrRange.Value = payload[macIndex++];
 
-                    if( ValueInRange( channelIndex, 3, LORA_MAX_NB_CHANNELS - 1 ) == false )
-
+                    LoRaMacState |= MAC_TX_CONFIG;
+                    if( chParam.Frequency == 0 )
                     {
-                        status &= 0xFE; // Channel frequency KO
+                        if( channelIndex < 3 )
+                        {
+                            status &= 0xFC;
+                        }
+                        else
+                        {
+                            if( LoRaMacChannelRemove( channelIndex ) != LORAMAC_STATUS_OK )
+                            {
+                                status &= 0xFC;
+                            }
+                        }
                     }
-
-                    if( Radio.CheckRfFrequency( chParam.Frequency ) == false )
+                    else
                     {
-                        status &= 0xFE; // Channel frequency KO
+                        switch( LoRaMacChannelAdd( channelIndex, chParam ) )
+                        {
+                            case LORAMAC_STATUS_OK:
+                            {
+                                break;
+                            }
+                            case LORAMAC_STATUS_FREQUENCY_INVALID:
+                            {
+                                status &= 0xFE;
+                                break;
+                            }
+                            case LORAMAC_STATUS_DATARATE_INVALID:
+                            {
+                                status &= 0xFD;
+                                break;
+                            }
+                            case LORAMAC_STATUS_FREQ_AND_DR_INVALID:
+                            {
+                                status &= 0xFC;
+                                break;
+                            }
+                            default:
+                            {
+                                status &= 0xFC;
+                                break;
+                            }
+                        }
                     }
-
-                    if( LoRaMacChannelAdd( channelIndex, chParam ) != LORAMAC_STATUS_OK )
-                    {
-                        status &= 0xFD; // Datarate range KO
-                    }
+                    LoRaMacState &= ~MAC_TX_CONFIG;
 #endif
                     AddMacCommand( MOTE_MAC_NEW_CHANNEL_ANS, status, 0 );
                 }
@@ -2291,7 +2359,16 @@
     }
 
     // Select channel
-    dutyCycleTimeOff = SetNextChannel( );
+    while( SetNextChannel( &dutyCycleTimeOff ) == false )
+    {
+        // Set the default datarate
+        ChannelsDatarate = ChannelsDefaultDatarate;
+
+#if defined( USE_BAND_433 ) || defined( USE_BAND_780 ) || defined( USE_BAND_868 )
+        // Re-enable default channels LC1, LC2, LC3
+        ChannelsMask[0] = ChannelsMask[0] | ( LC( 1 ) + LC( 2 ) + LC( 3 ) );
+#endif
+    }
 
     // Schedule transmission of frame
     if( dutyCycleTimeOff == 0 )
@@ -2365,6 +2442,8 @@
                 return LORAMAC_STATUS_NO_NETWORK_JOINED; // No network has been joined yet
             }
 
+            fCtrl->Bits.AdrAckReq = AdrNextDr( fCtrl->Bits.Adr, true, &ChannelsDatarate );
+
             if( ValidatePayloadLength( fBufferSize, ChannelsDatarate, MacCommandsBufferIndex ) == false )
             {
                 return LORAMAC_STATUS_LENGTH_ERROR;
@@ -2379,8 +2458,6 @@
                 fCtrl->Bits.Ack = 1;
             }
 
-            fCtrl->Bits.AdrAckReq = AdrNextDr( fCtrl->Bits.Adr, true, &ChannelsDatarate );
-
             LoRaMacBuffer[pktHeaderLen++] = ( LoRaMacDevAddr ) & 0xFF;
             LoRaMacBuffer[pktHeaderLen++] = ( LoRaMacDevAddr >> 8 ) & 0xFF;
             LoRaMacBuffer[pktHeaderLen++] = ( LoRaMacDevAddr >> 16 ) & 0xFF;
@@ -2513,6 +2590,7 @@
     MlmeConfirm.TxTimeOnAir = TxTimeOnAir;
 
     // Starts the MAC layer status check timer
+    TimerSetValue( &MacStateCheckTimer, MAC_STATE_CHECK_TIMEOUT );
     TimerStart( &MacStateCheckTimer );
 
     // Send now
@@ -3048,117 +3126,142 @@
 
 LoRaMacStatus_t LoRaMacChannelAdd( uint8_t id, ChannelParams_t params )
 {
+#if ( defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID ) )
+    return LORAMAC_STATUS_PARAMETER_INVALID;
+#else
+    bool datarateInvalid = false;
+    bool frequencyInvalid = false;
+    uint8_t band = 0;
+
+    // The id must not exceed LORA_MAX_NB_CHANNELS
     if( id >= LORA_MAX_NB_CHANNELS )
     {
         return LORAMAC_STATUS_PARAMETER_INVALID;
     }
+    // Validate if the MAC is in a correct state
     if( ( LoRaMacState & MAC_TX_RUNNING ) == MAC_TX_RUNNING )
     {
-        return LORAMAC_STATUS_BUSY;
+        if( ( LoRaMacState & MAC_TX_CONFIG ) != MAC_TX_CONFIG )
+        {
+            return LORAMAC_STATUS_BUSY;
+        }
     }
+    // Validate the datarate
     if( ( params.DrRange.Fields.Min > params.DrRange.Fields.Max ) ||
         ( ValueInRange( params.DrRange.Fields.Min, LORAMAC_MIN_DATARATE,
                         LORAMAC_MAX_DATARATE ) == false ) ||
         ( ValueInRange( params.DrRange.Fields.Max, LORAMAC_MIN_DATARATE,
                         LORAMAC_MAX_DATARATE ) == false ) )
     {
-        return LORAMAC_STATUS_PARAMETER_INVALID;
+        datarateInvalid = true;
     }
 
-    params.Band = 0;
-
-#if ( defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID ) )
-    return LORAMAC_STATUS_PARAMETER_INVALID;
-#else
-#if defined( USE_BAND_433 ) || defined( USE_BAND_780 )
-    Channels[id] = params;
-    Channels[id].Band = 0; // No duty cycle on EU433 and CN470 bands
-#elif defined( USE_BAND_868 )
-    Channels[id] = params;
-    if( ( Channels[id].Frequency >= 865000000 ) && ( Channels[id].Frequency <= 868000000 ) )
+#if defined( USE_BAND_433 ) || defined( USE_BAND_780 ) || defined( USE_BAND_868 )
+    if( id < 3 )
     {
-        if( Channels[id].Band != BAND_G1_0 )
+        if( params.Frequency != Channels[id].Frequency )
         {
-            Channels[id].Band = BAND_G1_0;
+            frequencyInvalid = true;
+        }
+
+        if( params.DrRange.Fields.Min > LORAMAC_DEFAULT_DATARATE )
+        {
+            datarateInvalid = true;
+        }
+        if( ValueInRange( params.DrRange.Fields.Max, DR_5, LORAMAC_MAX_DATARATE ) == false )
+        {
+            datarateInvalid = true;
         }
     }
-    else if( ( Channels[id].Frequency > 868000000 ) && ( Channels[id].Frequency <= 868600000 ) )
+#endif
+
+    // Validate the frequency
+    if( ( Radio.CheckRfFrequency( params.Frequency ) == true ) && ( params.Frequency > 0 ) && ( frequencyInvalid == false ) )
     {
-        if( Channels[id].Band != BAND_G1_1 )
+#if defined( USE_BAND_868 )
+        if( ( params.Frequency >= 865000000 ) && ( params.Frequency <= 868000000 ) )
         {
-            Channels[id].Band = BAND_G1_1;
+            band = BAND_G1_0;
         }
-    }
-    else if( ( Channels[id].Frequency >= 868700000 ) && ( Channels[id].Frequency <= 869200000 ) )
-    {
-        if( Channels[id].Band != BAND_G1_2 )
+        else if( ( params.Frequency > 868000000 ) && ( params.Frequency <= 868600000 ) )
         {
-            Channels[id].Band = BAND_G1_2;
+            band = BAND_G1_1;
         }
-    }
-    else if( ( Channels[id].Frequency >= 869400000 ) && ( Channels[id].Frequency <= 869650000 ) )
-    {
-        if( Channels[id].Band != BAND_G1_3 )
+        else if( ( params.Frequency >= 868700000 ) && ( params.Frequency <= 869200000 ) )
         {
-            Channels[id].Band = BAND_G1_3;
+            band = BAND_G1_2;
+        }
+        else if( ( params.Frequency >= 869400000 ) && ( params.Frequency <= 869650000 ) )
+        {
+            band = BAND_G1_3;
         }
-    }
-    else if( ( Channels[id].Frequency >= 869700000 ) && ( Channels[id].Frequency <= 870000000 ) )
-    {
-        if( Channels[id].Band != BAND_G1_4 )
+        else if( ( params.Frequency >= 869700000 ) && ( params.Frequency <= 870000000 ) )
         {
-            Channels[id].Band = BAND_G1_4;
+            band = BAND_G1_4;
         }
+        else
+        {
+            frequencyInvalid = true;
+        }
+#endif
     }
     else
     {
-        Channels[id].Frequency = 0;
-        Channels[id].DrRange.Value = 0;
+        frequencyInvalid = true;
+    }
+
+    if( ( datarateInvalid == true ) && ( frequencyInvalid == true ) )
+    {
+        return LORAMAC_STATUS_FREQ_AND_DR_INVALID;
     }
-#else
-    #error "Please define a frequency band in the compiler options."
-#endif
-    // Check if it is a valid channel
-    if( Channels[id].Frequency > 0 )
+    if( datarateInvalid == true )
+    {
+        return LORAMAC_STATUS_DATARATE_INVALID;
+    }
+    if( frequencyInvalid == true )
     {
-        // Activate the newly created channel
-        if( id < 16 )
-        {
-            ChannelsMask[0] |= 1 << id;
-        }
+        return LORAMAC_STATUS_FREQUENCY_INVALID;
     }
 
+    // Every parameter is valid, activate the channel
+    Channels[id] = params;
+    Channels[id].Band = band;
+    ChannelsMask[0] |= ( 1 << id );
+
     return LORAMAC_STATUS_OK;
 #endif
 }
 
 LoRaMacStatus_t LoRaMacChannelRemove( uint8_t id )
 {
+#if defined( USE_BAND_433 ) || defined( USE_BAND_780 ) || defined( USE_BAND_868 )
     if( ( LoRaMacState & MAC_TX_RUNNING ) == MAC_TX_RUNNING )
     {
-        return LORAMAC_STATUS_BUSY;
+        if( ( LoRaMacState & MAC_TX_CONFIG ) != MAC_TX_CONFIG )
+        {
+            return LORAMAC_STATUS_BUSY;
+        }
     }
-#if ( defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID ) )
-    if( id < 64 )
+
+    if( id < 3 )
     {
-        if( CountNbEnabled125kHzChannels( ChannelsMask ) <= 6 )
+        return LORAMAC_STATUS_PARAMETER_INVALID;
+    }
+    else
+    {
+        // Remove the channel from the list of channels
+        Channels[id] = ( ChannelParams_t ){ 0, { 0 }, 0 };
+        
+        // Disable the channel as it doesn't exist anymore
+        if( DisableChannelInMask( id, ChannelsMask ) == false )
         {
             return LORAMAC_STATUS_PARAMETER_INVALID;
         }
     }
-#else
-    if( id < 3 )
-    {
-        return LORAMAC_STATUS_PARAMETER_INVALID;
-    }
+    return LORAMAC_STATUS_OK;
+#elif ( defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID ) )
+    return LORAMAC_STATUS_PARAMETER_INVALID;
 #endif
-
-    if( DisableChannelInMask( id, ChannelsMask ) == false )
-    {
-        return LORAMAC_STATUS_PARAMETER_INVALID;
-    }
-
-    return LORAMAC_STATUS_OK;
 }
 
 LoRaMacStatus_t LoRaMacMulticastChannelLink( MulticastParams_t *channelParam )
@@ -3283,6 +3386,14 @@
             IsLoRaMacNetworkJoined = false;
 
 #if defined( USE_BAND_915 ) || defined( USE_BAND_915_HYBRID )
+#if defined( USE_BAND_915 )
+            // Re-enable 500 kHz default channels
+            ChannelsMask[4] = 0x00FF;
+#else // defined( USE_BAND_915_HYBRID )
+            // Re-enable 500 kHz default channels
+            ChannelsMask[4] = 0x0001;
+#endif
+
             static uint8_t drSwitch = 0;
 
             if( ( ++drSwitch & 0x01 ) == 0x01 )
@@ -3362,7 +3473,7 @@
         {
             readyToSend = true;
             AckTimeoutRetriesCounter = 1;
-            AckTimeoutRetries = mcpsRequest->Req.Confirmed.nbRetries;
+            AckTimeoutRetries = mcpsRequest->Req.Confirmed.NbTrials;
 
             macHdr.Bits.MType = FRAME_TYPE_DATA_CONFIRMED_UP;
             fPort = mcpsRequest->Req.Confirmed.fPort;