Can i use lwm2m library of iot sdk used over UART instead of 6lowpan ble interface? Please let me know how i can use this iot sdk over UART instead of 6lowpan? i want to use gsm module on the place of raspberry pi border router..

[abhishek.drish]

I want to communicate with lwm2m server using gsm module and nrf52832 as lwm2m client. i installed lwm2m demo server  over linux machine.

[Hung Bui]

Hi Abhishek, 

We have some question regarding your setup. 

- Which protocol is on the UART communication between the GSM module and the nRF52 ? Is it AT commands ? 

- Where should the IP stack implemented ? Is it on the GSM module or it's on the nRF52 ? 

[abhishek.drish]

Hi hung bui,

-for first yes i am tried to use AT commands between GSM module and nRF52 by using app_uart.h.

- everithing is in nRF52 code like ip stack , server uri , lwm2m setup object callback and declaration. 

[Hung Bui]

Hi Abhishek, 

The current implementation in our IoT SDK doesn't have the IP stack running on the nRF52. It's on the gateway as shown here.

I assume you don't use BLE for this communication at all ? 

I got a suggestion from our developer with the following diagram: 

If you don't use BLE 6LowPAN then only the green part is needed. 

We suggest you to implement the IP stack driver with network interface, for example lwIP in our older IoT SDK: https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.iotsdk.v0.9.0/iot_sdk_user_guides_lwip_stack.html?cp=7_4_4_12

The network interface here would be useful: https://github.com/ARMmbed/mbed-os/tree/master/features/lwipstack

Please be aware that this is not something we can support and make an example for you. And you would need to implement based on what we have. And we believe there should be someone else already implemented something similar. 

For example: https://github.com/ARMmbed/mbed-os-example-cellular

https://github.com/zephyrproject-rtos/zephyr/pull/6344

[abhishek.drish]

Hi Hung bui,

I am working on your suggestions and try to add app_uart .h  library in lwm2m client example present in IoT_sdk 0.9.0 but getting and fatal error and module reset again and again after called uart init function i.e app_uart_fifo_init function present in app_uart library. which library use in lwm2m example in the place of IPSP  layer please let me know or there is any other way for doing this. I also tried to use libuarte library but not getting success. please let me know the way how I go forward in this. 

[Hung Bui]

Hi Abhishek, 

Please try to debug. Which exact function threw the error ? Which error code ? 
Please follow the debug guide here.