nRF9160: LTE Sensor Gateway

[Marshed]

I have been using nRF9160: LTE Sensor Gateway to send data from nRF52832 and it all seems to work fine. However whenever i switch off the nRF52832 I receive an error as attached below. 

Can you anyone assist on how to solve this error? 

the nRF9160 should keep a stable connection whether it is connected to nRF52832 or not, but with this error the LTE connection is disabled whenever bluetooth device is disconnected. 

please assist.

[Susheel Nuguru]

You can look into the map file and see which function resides at 0xe8c8 to get a better context on the hardfault

[Marshed]

and where can i find the map file?

[Marte Myrvold]

You have to search for only e8c8, without 0x

[Marshed]

It seems that snprintf function resides here 

e8c4: b513 push {r0, r1, r4, lr}
len = snprintf(buf, sizeof(buf), "%d", test);
e8c6: 2106 movs r1, #6
e8c8: f8b2 3001 ldrh.w r3, [r2, #1]

how can i fix this problem

[Marte Myrvold]

Is it possible that you are sending something invalid to snprintf? You can try to print buf and sizeof(buf) using printk in order to see what you are actually sending to snprintf.

[Marshed]

when the bluetooth device is connected, I am sending the data to snprintf and it is correct data, and the programm is running fine. when the bluetooth device is disconnected, I do not expect this function to be called as nothing is being received from the bluetooth device. 

[Susheel Nuguru]

Well put a. Breakpoint in disassembly at this function to see the call stack of how the control reached there.

Check if buf is uninitialized or NULL

[Marshed]

and how do i do that? put a breakpoint in disassembly and see the call stack, and check if but is uninitialized?

[Marshed]

I am still surprised why is the on received function called when gatt is disconnected?

can you assist?

[Susheel Nuguru]

That does not make sense to me either. The call stack seems to be incomplete or corrupt. Are you sure that you have compiled the application with no optimizations in the compiler?

[Marshed]

I fixed it, by putting a condition in the beginning of the function 

static u8_t on_received(struct bt_conn *conn,
struct bt_gatt_subscribe_params *params,
const void *data, u16_t length)
{
if (length > 0) {