Lora config at 433MHz

[malarab]

Hello,

I used a GFSK configuration with 433MHz and it is work very well,

I try now to migrate to Lora modulation. i used a basic config, but the receiver on the other side receive less then 1% of sent frames ! (even transmitter and receiver are very close)

is anybody has advice to improve communication ?

 

[malarab]

I finally found that the lack of detection is not due to Lora configuration.

but my receiver (I dont know why) receive a hardfault interruption after receiving !

it is not the case for the transmitter

I always need your help, maybe i have messed something in receiver config !

[malarab]

last update after multiple debugging :

1 - when i set fix payload length in tx and rx config, i have a crc error in detected frame, i detect wrong data, than a hardfault.

2 - when i set variable payload length, i don't have the hardfault, but a cannot detect all frame (less then 1% are detected) and when i detect, i usually have a header error

i set the same config for the transmitter and the receiver.

[malarab]

I tried to configure lora modulation on an other way, but always the same problem !

pleas find the code below

 

[Louis AUDOLY]

Hello @malarab​ ,

Can you try with an example project from STM32Cube_FW_WL_V1.2.0, like SubGHz_Phy_PingPong to see if you achieve to make it work with LoRa modulation in 433MHz.

Don't forget to add this line in "subghz_phy_app.h" to select the right frequency :

#define REGION_EU433

Let me know the result

Best regards

Louis

[malarab]

Hi Loius,

Thank you for your answer

1 - Yes, PingPong example is working,

2 - I have resolved the problem of HardFault : in fact i do not use HAL drivers, so i programmed my own low-level code, i missed some callback function for LoRa (because i do not use them in GFSK). putting these function again the HardFault problem is resolved.

3 - I steel have problem on receiving : i cannot receive all sent frames !

4 - I am sur that transition is ok, because i detect all data with PingPong receiver.

I am reviewing my low level code to verify that all is ok ...

[malarab · Accepted solution]

finally i resolved the problem :

in fact, i made an application without hal drivers, just ll drivers. so, i have write my own code to interface radio drivers with subghzSPI inspired by hal_subghz.

but for some reason, it worked on GFSK modulation but no in LoRa modulation.

finally, i implemented hal_subghz file and necessary definitions to run it, and it is working done :)