lorawan1v1 - LoRaWAN end device MAC layer for SX1272 and SX127…

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LoRaWAN end device MAC layer for SX1272 and SX1276. Supports LoRaWAN-1.0 and LoRaWAN-1.1

Dependents: LoRaWAN-SanJose_Bootcamp LoRaWAN-grove-cayenne LoRaWAN-classC-demo LoRaWAN-grove-cayenne ... more

radio chip selection

Radio chip driver is not included, because two options are available.
If you're using SX1272 or SX1276, then import sx127x driver into your program.
if you're using SX1261 or SX1262, then import sx126x driver into your program.
If you're using NAmote72 or Murata discovery, then you must import only sx127x driver.

application project requirements

This library requires mbed TLS to be enabled.
The file mbed_app.json must be present in the project using this library:

{
    "macros": [ "MBEDTLS_CMAC_C" ]
}

regional PHY selection

All end device configuration is done in Commissioning.h, define desired radio frequency band of operation in this header file.
Commissioning.h is located in the application using this library.

end device provisioning

End device is provisioned by editing Commissioning.h in the application which is using this library
To use LoRaWAN-1.0 OTA: make sure LORAWAN_ROOT_APPKEY is undefined.
To use LoRaWAN-1.1 OTA, define LORAWAN_ROOT_APPKEY.
To select OTA operation, define LORAWAN_JOIN_EUI, then LORAWAN_DEVICE_EUI must be defined, along with root key(s).
To select ABP operation, undefine LORAWAN_JOIN_EUI: then define session keys

	LoRaWAN 1.0 name	LoRaWAN 1.1 name	Comissioning.h defne	description
OTA	DevEUI	DevEUI	`LORAWAN_DEVICE_EUI`	uniquely identifies end device
OTA	AppEUI	JoinEUI	`LORAWAN_JOIN_EUI`
OTA	AppKey	NwkKey	`LORAWAN_ROOT_NWKKEY`	root key for network server
OTA	(note 1)	AppKey	`LORAWAN_ROOT_APPKEY`	root key for application server
ABP	NwkSKey	(note 3)	`LORAWAN_FNwkSIntKey`	network session key
ABP	(note 2)	SNwkSIntKey	`LORAWAN_SNwkSIntKey`	mac layer network integrity key
ABP	(note 2)	NwkSEncKey	`LORAWAN_NwkSEncKey`	network session encryption key
ABP	(note 2)	FNwkSIntKey	`LORAWAN_FNwkSIntKey`	forwarding network session integrity key
ABP	AppSKey	AppSKey	`LORAWAN_APPSKEY`	application session encryption key

(note 1): LoRaWAN-1.0 OTA uses a single root key for both network server and application server.

In LoRaWAN-1.0 OTA: the single root AppKey is used to generate NwkSkey and AppSKey.
(note 2): In LoRaWAN-1.0 (both OTA and ABP) SNwkSIntKey, NwkSEncKey. FNwkSIntKey are of same value and are collectively known as NwkSKey.
(note 3): LoRaWAN-1.0 uses single network session key, LoRaWAN-1.1 uses 3 network session keys. Both use a unique application session key.

In LoRaWAN-1.1 OTA: the root NwkKey is used to generate SNwkSIntKey, NwkSEncKey, FNwkSIntKey
In LoRaWAN-1.1 OTA: the root AppKey is used to generate AppSKey

in ABP mode, the DevAddr, and session keys are fixed (never change), and frame counters never reset to zero.
ABP operation has no concept of: root keys, or DevEUI or JoinEUI/AppEUI.
in OTA mode, the DevAddr and session keys are assigned at join procedure, and frame counters reset at join.

eeprom

This library includes eeprom driver to support non-volatile storage required by LoRaWAN specification.
Currently eeprom is implemented for STM32L1 family and STM32L0 family.
Writing of values are wear-leveled to increase endurance; each write operation circulates across several memory locations. A read operation returns the highest value found. This simple method is used for sequence numbers which only increase.

value name	used in
DevNonce	OTA	for Join request (note 1)
RJcount1	OTA	for ReJoin Type 1 request
FCntUp	ABP	uplink frame counter
NFCntDown	ABP	downlink frame counter
AFCntDown	ABP	downlink frame counter

AFCntDown is only used in LoRaWAN-1.1 when application payload is present in downlink and FPort > 0.
NFCntDown is used in LoRaWAN-1.1 when FPort is zero in downlink or application payload not present.
NFCntDown is the only downlink frame counter used in LoRaWAN-1.0
(note 1) OTA DevNonce is random number in LoRaWAN-1.0, therefore not stored in eeprom. DevNonce in LoRaWAN-1.1 is forever increasing (non-volatile) number upon each join request,.
RJcount0 is only stored in RAM because the value resets upon new session from JoinAccept, therefore not stored in eeprom.
Frame counters in OTA mode reset upon new session in join request, therefore are stored in RAM instead of eeprom for OTA.

radio driver support

When SX127x driver is used, both SX1272 and SX1276 are supported without defining at compile time. The chip is detected at start-up.
Supported radio platforms:

Alternately, when SX126x driver is imported, the SX126xDVK1xAS board is used.

low-speed clock oscillator selection

LoRaWAN uses 32768Hz crystal to permit low-power operation.
However, some mbed targets might revert to low-speed internal oscillator, which is not accurate enough for LoRaWAN operation.
An oscillator check is performed at initialization; program will not start if internal oscillator is used.
To force LSE watch crystal, add to mbed_app.json

{
    "macros": [ "MBEDTLS_CMAC_C" ],
    "target_overrides": {
        "<your-target>": {
            "target.lse_available": true
        }
    }
}

Diff: mac/region_us915.cpp

Revision:: 3:eb174e10afbb
Parent:: 0:6b3ac9c5a042
Child:: 7:4b6f960dcca2

--- a/mac/region_us915.cpp	Thu Mar 01 17:27:30 2018 +0000
+++ b/mac/region_us915.cpp	Mon Mar 05 16:49:15 2018 -0800
@@ -137,26 +137,6 @@
     return chanMaskState;
 }
 
-void ReenableChannels( uint16_t mask, uint16_t* channelsMask )
-{
-    uint16_t blockMask = mask;
-
-    for( uint8_t i = 0, j = 0; i < 4; i++, j += 2 )
-    {
-        channelsMask[i] = 0;
-        if( ( blockMask & ( 1 << j ) ) != 0 )
-        {
-            channelsMask[i] |= 0x00FF;
-        }
-        if( ( blockMask & ( 1 << ( j + 1 ) ) ) != 0 )
-        {
-            channelsMask[i] |= 0xFF00;
-        }
-    }
-    channelsMask[4] = blockMask;
-    channelsMask[5] = 0x0000;
-}
-
 void region_adr_request(adr_t* adr)
 {
     if( adr->chMaskCntl == 6 )
@@ -214,30 +194,9 @@
     }
 }
 
-void
-region_adr_next_dr(int8_t* dr, bool update)
+uint8_t region_CountNbEnabledChannels()
 {
-    if( ( *dr > LORAMAC_TX_MIN_DATARATE ) && ( *dr == DR_8 ) )
-    {
-        *dr = DR_4;
-    }
-    else if( *dr > LORAMAC_TX_MIN_DATARATE )
-    {
-        (*dr)--;
-    }
-    if( *dr == LORAMAC_TX_MIN_DATARATE )
-    {
-        if( update == true )
-        {
-#if defined( USE_BAND_915 )
-            // Re-enable default channels
-            memcpy( ( uint8_t* )LoRaMacParams.ChannelsMask, ( uint8_t* )LoRaMacParamsDefaults.ChannelsMask, sizeof( LoRaMacParams.ChannelsMask ) );
-#else // defined( USE_BAND_915_HYBRID )
-            // Re-enable default channels
-            ReenableChannels( LoRaMacParamsDefaults.ChannelsMask[4], LoRaMacParams.ChannelsMask );
-#endif
-        }
-    }
+    return CountNbEnabled125kHzChannels(LoRaMacParams.ChannelsMask) + CountBits(LoRaMacParams.ChannelsMask[4], 16);
 }
 
 uint8_t CountNbEnabled125kHzChannels( uint16_t *channelsMask )
@@ -336,24 +295,33 @@
     }
 }
 
+#define RECEIVE_DELAY2_us                           2000000
+#define JOIN_ACCEPT_DELAY1_us                          5000000
+#define JOIN_ACCEPT_DELAY2_us                          6000000
+const LoRaMacParams_t LoRaMacParamsDefaults = {
+    /* int8_t ChannelsTxPower; */   LORAMAC_DEFAULT_TX_POWER,
+    /* int8_t ChannelsDatarate;*/   LORAMAC_DEFAULT_DATARATE,
+    /* uint32_t MaxRxWindow_us;*/   MAX_RX_WINDOW_us,
+    /* uint32_t ReceiveDelay1_us;*/ RECEIVE_DELAY1_us,
+    /* uint32_t ReceiveDelay2_us;*/ RECEIVE_DELAY2_us,
+#ifdef LORAWAN_JOIN_EUI
+    /* uint32_t JoinAcceptDelay1_us;*/  JOIN_ACCEPT_DELAY1_us,
+    /* uint32_t JoinAcceptDelay2_us;*/  JOIN_ACCEPT_DELAY2_us,
+#endif /* LORAWAN_JOIN_EUI  */
+    /* uint8_t NbTrans;*/   1,
+    /* uint8_t Rx1DrOffset;*/   0,
+    /* Rx2ChannelParams_t Rx2Channel;*/ RX_WND_2_CHANNEL,
+#if defined( USE_BAND_915 )
+    /* uint16_t ChannelsMask[6];*/ { 0xffff, 0xffff, 0xffff, 0xffff, 0x00ff, 0x0000},
+    /* uint8_t NbEnabledChannels;*/ 72,
+#elif defined( USE_BAND_915_HYBRID )
+    /* uint16_t ChannelsMask[6];*/ { 0x00ff, 0x0000, 0x0000, 0x0000, 0x0001, 0x0000},
+    /* uint8_t NbEnabledChannels;*/ 9
+#endif
+};
+
 void region_mac_init()
 {
-#if defined( USE_BAND_915 )
-    LoRaMacParamsDefaults.ChannelsMask[0] = 0xFFFF;
-    LoRaMacParamsDefaults.ChannelsMask[1] = 0xFFFF;
-    LoRaMacParamsDefaults.ChannelsMask[2] = 0xFFFF;
-    LoRaMacParamsDefaults.ChannelsMask[3] = 0xFFFF;
-    LoRaMacParamsDefaults.ChannelsMask[4] = 0x00FF;
-    LoRaMacParamsDefaults.ChannelsMask[5] = 0x0000;
-#elif defined( USE_BAND_915_HYBRID )
-    LoRaMacParamsDefaults.ChannelsMask[0] = 0x00FF;
-    LoRaMacParamsDefaults.ChannelsMask[1] = 0x0000;
-    LoRaMacParamsDefaults.ChannelsMask[2] = 0x0000;
-    LoRaMacParamsDefaults.ChannelsMask[3] = 0x0000;
-    LoRaMacParamsDefaults.ChannelsMask[4] = 0x0001;
-    LoRaMacParamsDefaults.ChannelsMask[5] = 0x0000;
-#endif
-
     // 125 kHz channels
     for( uint8_t i = 0; i < LORA_MAX_NB_CHANNELS - 8; i++ )
     {
@@ -370,6 +338,46 @@
     }
 }
 
+int8_t
+region_LimitTxPower( int8_t txPower )
+{
+    int8_t resultTxPower = txPower;
+ 
+    if( ( LoRaMacParams.ChannelsDatarate == DR_4 ) ||
+        ( ( LoRaMacParams.ChannelsDatarate >= DR_8 ) && ( LoRaMacParams.ChannelsDatarate <= DR_13 ) ) )
+    {// Limit tx power to max 26dBm
+        resultTxPower =  MAX( txPower, TX_POWER_26_DBM );
+    }
+    else
+    {
+        if( CountNbEnabled125kHzChannels( LoRaMacParams.ChannelsMask ) < 50 )
+        {// Limit tx power to max 21dBm
+            resultTxPower = MAX( txPower, TX_POWER_20_DBM );
+        }
+    }
+    return resultTxPower;
+}
+
+#ifdef LORAWAN_JOIN_EUI
+int8_t
+region_AlternateDatarate( uint16_t nbTrials )
+{
+    if (region_CountNbEnabledChannels() < LoRaMacParamsDefaults.NbEnabledChannels) {
+        memcpy(LoRaMacParams.ChannelsMask, LoRaMacParamsDefaults.ChannelsMask, sizeof(LoRaMacParams.ChannelsMask));
+        LoRaMacParams.NbEnabledChannels = LoRaMacParamsDefaults.NbEnabledChannels;
+    }
+
+    if( ( nbTrials & 0x01 ) == 0x01 )
+    {
+        return DR_4;
+    }
+    else
+    {
+        return DR_0;
+    }
+}
+#endif /* LORAWAN_JOIN_EUI  */
+
 void region_session_start(LoRaMacEventInfoStatus_t status) { }
 
 #endif /* USE_BAND_915_HYBRID || USE_BAND_915 */

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Repository details

Type:	Library
Created:	28 Feb 2018
Imports:	60
Forks:	0
Commits:	13
Dependents:	9
Dependencies:	1
Followers:	9