Hi,
I'm looking to use the nRF9160 DK as an IoT Bluetooth Gateway as listed on the nRF9160's product page. Basically, I am tasked with connecting two nRF52840's (both in GATT client mode) to an nRF9160 DK (in GATT server mode) using Bluetooth 5 and then have cellular connection via the nRF9160 to connect to the Cloud and push up metrics/telemetry/etc.
My Question is the following: It seems the nRF9160 does NOT allow main program execution if there is NO cellular connection. Is it possible to allow program execution on the nRF9160 to continue without cellular connection? Reasoning for needing this is that the end use application requires collecting data (telemetry, metrics, etc.) if there is no cellular connection (offline).
After reading this following documentation: https://infocenter.nordicsemi.com/index.jsp?topic=%2Fug_nrf91_dk%2FUG%2Fnrf91_DK%2Fintro.html&cp=2_0_2
"Application and modem domains are interacting through interprocessor communication (IPC) mechanism. LTE modem is accessible to user through the modem API.
The application processor is the master in the system and responsible for starting and stopping of the modem. LTE modem enables the clocks and power required for its own operation. Shared resources, such as e.g. clocks, are handled within the platform and require no user involvement. In cases where a hard fault is detected in the modem, the application domain will perform a hard reset for the modem."
Note the last sentence, which is the case and behavior currently when I power on the nRF9160 DK and it sees no cellular internet connection.
I have followed the steps outlined in the README.rst within the "lte_ble_gateway" sample project in the nRF9160 DK sample projects to setup the nRF9160 DK:
"Programming the sample
======================
When you connect the nRF9160 DK board to your computer, three virtual serial ports (USB CDC class) should appear.
The first port is connected to the main controller (nRF9160) on the board, while the second port is connected to the board controller (nRF52840).
Before you program the sample application onto the main controller, you must program the :ref:`zephyr:bluetooth-hci-uart-sample` sample onto the board controller:
1. Put the **SW5** switch (marked debug/prog) in the **NRF52** position to program the board controller.
#. Build the :ref:`zephyr:bluetooth-hci-uart-sample` sample for the nrf52840_pca10090 board and program it.
#. Verify that the sample was programmed successfully by connecting to the second serial port with a terminal emulator (for example, PuTTY) and checking the output.
See :ref:`putty` for the required settings.
After programming the board controller, you must program the :ref:`secure_boot` sample and the LTE Sensor Gateway sample to the main controller:
1. Put the **SW5** switch (marked debug/prog) in the **NRF91** position to program the main controller.
#. Build the :ref:`secure_boot` sample and program it.
#. Build the LTE Sensor Gateway sample (this sample) and program it.
#. Verify that the sample was programmed successfully by connecting to the first serial port with a terminal emulator (for example, PuTTY) and checking the output.
See :ref:`putty` for the required settings."
Debugging via Embbedded Studio reveals the nRF9160 DK is "stuck" in a library function called "interface_socket_wait".
Thank you!
