Applied SX1272 and SX1276 radios errata note 3.1 to the radio drivers implementation.

Author: mluis1

src/radio/sx1272/sx1272.c

@@ -1457,11 +1457,17 @@ void SX1272OnDio1Irq( void* context )
                         SX1272.Settings.FskPacketHandler.Size = SX1272Read( REG_PAYLOADLENGTH );
                     }
                 }
-
-                if( ( SX1272.Settings.FskPacketHandler.Size - SX1272.Settings.FskPacketHandler.NbBytes ) > SX1272.Settings.FskPacketHandler.FifoThresh )
+                // ERRATA 3.1 - PayloadReady Set for 31.25ns if FIFO is Empty
+                //
+                //              When FifoLevel interrupt is used to offload the
+                //              FIFO, the microcontroller should  monitor  both
+                //              PayloadReady  and FifoLevel interrupts, and
+                //              read only (FifoThreshold-1) bytes off the FIFO
+                //              when FifoLevel fires
+                if( ( SX1272.Settings.FskPacketHandler.Size - SX1272.Settings.FskPacketHandler.NbBytes ) >= SX1272.Settings.FskPacketHandler.FifoThresh )
                 {
-                    SX1272ReadFifo( ( RxTxBuffer + SX1272.Settings.FskPacketHandler.NbBytes ), SX1272.Settings.FskPacketHandler.FifoThresh );
-                    SX1272.Settings.FskPacketHandler.NbBytes += SX1272.Settings.FskPacketHandler.FifoThresh;
+                    SX1272ReadFifo( ( RxTxBuffer + SX1272.Settings.FskPacketHandler.NbBytes ), SX1272.Settings.FskPacketHandler.FifoThresh - 1 );
+                    SX1272.Settings.FskPacketHandler.NbBytes += SX1272.Settings.FskPacketHandler.FifoThresh - 1;
                 }
                 else
                 {

src/radio/sx1276/sx1276.c

@@ -1637,10 +1637,17 @@ void SX1276OnDio1Irq( void* context )
                     }
                 }
 
-                if( ( SX1276.Settings.FskPacketHandler.Size - SX1276.Settings.FskPacketHandler.NbBytes ) > SX1276.Settings.FskPacketHandler.FifoThresh )
+                // ERRATA 3.1 - PayloadReady Set for 31.25ns if FIFO is Empty
+                //
+                //              When FifoLevel interrupt is used to offload the
+                //              FIFO, the microcontroller should  monitor  both
+                //              PayloadReady  and FifoLevel interrupts, and
+                //              read only (FifoThreshold-1) bytes off the FIFO
+                //              when FifoLevel fires
+                if( ( SX1276.Settings.FskPacketHandler.Size - SX1276.Settings.FskPacketHandler.NbBytes ) >= SX1276.Settings.FskPacketHandler.FifoThresh )
                 {
-                    SX1276ReadFifo( ( RxTxBuffer + SX1276.Settings.FskPacketHandler.NbBytes ), SX1276.Settings.FskPacketHandler.FifoThresh );
-                    SX1276.Settings.FskPacketHandler.NbBytes += SX1276.Settings.FskPacketHandler.FifoThresh;
+                    SX1276ReadFifo( ( RxTxBuffer + SX1276.Settings.FskPacketHandler.NbBytes ), SX1276.Settings.FskPacketHandler.FifoThresh - 1 );
+                    SX1276.Settings.FskPacketHandler.NbBytes += SX1276.Settings.FskPacketHandler.FifoThresh - 1;
                 }
                 else
                 {