[STM32WLE5JC][LoRaWan - End_Node] How to change device_eui, epp_eui, app_key from program ?

[SC26]

Hi,

I have build a custom application from end_node project example on LoRa-E5 board.

All works fine with comissioning from CubeMX.

But now I want to use values loaded from flash.

So I added 3 variables :

uint8_t device_eui[8];

uint8_t app_eui[8];

uint8_t app_key[16];

I can read/write values from flash.

But now : how to use this values for LoRa-Wan OTAA joining ???!!!!

How could this be sooooo hard to do ???!!!!!

Thanks for help.

[Andrew Neil]

The software does OTAA as-is - no changes needed. :beaming_face_with_smiling_eyes:

See this series of videos:

https://www.youtube.com/watch?v=vuc6914B0KM - Part 1; parts 2 & 3 follow

[SC26]

Hi,

I know OTAA is well done ... that's not my answer.

The question was : how to change End device commissioning parameters without rebuibind firmware for each device ?

( I already have read this parameters in variables from flash )

thanks.

[SC26]

I have look the 4 video ... not what I'm lokoing for ... he just edit identity.h to change commissioning parameters ...

[Andrew Neil]

As it tells you in those videos, the Device EUI is taken from the STM32's unique ID.

To change the other parameters, just look at where those values get used - use your IDE's browsing facilities - and supply your own instead.

[SC26]

I have try that ... And don't find.
So i ask here ...

[SC26]

The problem is to find where set parameters in the end_node example project.

Of course this must be in USER CODE BEGIN / USER CODE END section for not beiing overwrite by CubeMX on next code generation ...

[SC26]

In anycase : thanks for your answers ;)

[SC26]

Where am I ?

I have found in "se-identity.h" all the MX's #define :

#define LORAWAN_DEVICE_EUI                 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }

#define LORAWAN_JOIN_EUI                  { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 }

#define LORAWAN_APP_KEY                  00,00,00,00,00,00,00,00,00,00,00,00,00,00,00,00

And also found where they are used :

[ soft-sec.c :: 527 ]

SecureElementStatus_t SecureElementInit( SecureElementNvmData_t *nvm, SecureElementGetUniqueId seGetUniqueId )

But this section is not user-allowed.

I also see some tools functions :

SecureElementStatus_t SecureElementSetKey( KeyIdentifier_t keyID, uint8_t* key )

SecureElementStatus_t SecureElementSetDevEui( uint8_t* devEui )

SecureElementStatus_t SecureElementSetJoinEui( uint8_t* joinEui )

But I don't found how (from where) I can use this ...

[Andrew Neil]

@SC26​ "Of course this must be in USER CODE BEGIN / USER CODE END section for not beiing overwrite by CubeMX"

I'm not sure that the LoRaWAN code is subject to CubeMX modifications?

I don't use CubeMX, but it should be easy to do a test to see if your changes survive a re-generation...

[SC26]

Hi !

custom device_eui was pretty easy by editing GetUniqueId function (in sys_app.c :: 198 ).

Nice ! :grinning_face:

void GetUniqueId(uint8_t *id)
{
 /* USER CODE BEGIN GetUniqueId_1 */
	extern uint8_t device_eui[8];
	//
	for( int i=0 ; i<8 ; i++ )
	{
		id[i] = device_eui[i];
	}
 return;
 /* USER CODE END GetUniqueId_1 */

Now ... I need to do the same for other parameters :face_savoring_food:

I will check about MX overwriting code ...

[SC26]

OK, so ...

I found the way to custom eui/keys :

LoRaMac.c :: 4161

 // Initialize the Secure Element driver
 if( SecureElementInit( &Nvm.SecureElement, callbacks->GetUniqueId ) != SECURE_ELEMENT_SUCCESS ) /* ST_WORKAROUND: Add unique ID callback as input parameter */
 {
 return LORAMAC_STATUS_CRYPTO_ERROR;
 }
 
 // TEST : Set MY eui&keys
 {
 	extern uint8_t device_eui[8];
 	extern uint8_t app_eui[8];
 	extern uint8_t app_key[16];
 
 	SecureElementSetDevEui( device_eui );
 	SecureElementSetJoinEui( app_eui );
 	SecureElementSetKey( APP_KEY, app_key );
 }

This looks OK ... but the code is RESET after MX generation, maybe by editing library source code instead of my project ... but this is definitly not a solution ...

I will try this way, but if anybody have a better way, he is welcome !!!

[Dana Myers]

I believe these LmHandler functions are what you're looking for:

 LmHandlerGetDevEUI();

 LmHandlerGetNwkKey();

 LmHandlerGetAppKey();

Cheers,

Dana

[SC26]

Hi, yes, this looks fine, but I don't know from where can I call them to ensure they are used by LoRaWan middleware ... any advice ?