BLE CONNEXTION CUT REGULARY

[achraf]

Hello,

I have problems with my custom board nrf52832 , when I launch the uart connection and the processing of sending the data of my gps to the server to ble cut and stop adevertising and start
again ,what cause a the issue.
I have a connexion  with sim868 (gps and gprs) via UART(LIBUARTE) .
and connexion with my app via BLE , but I have THE Issue(the ble disconnect everytime the sim send the data to the server).

is it any priority things to avoid this or what ? , Ive did this : NRF_LIBUARTE_ASYNC_DEFINE(libuarte, 0, 2, 2, NRF_LIBUARTE_PERIPHERAL_NOT_USED, 255, 3);
is there any solution or something to resolve the ble cut connexion ?

I think because  I've done a lot of Process.
I'm with working with SES

[awneil]

achraf said:

the ble disconnect everytime the sim send the data to the server

Sounds like you have a power supply issue.

A GSM radio draws very large peaks of current when transmitting - likely this is causing a "brown out", which upsets the BLE connection.

Possibly also RF interference.

achraf said:

I think because  I've done a lot of Process

You think you might be causing a Watchdog reset?

The RESETREAS register gives the reason for a reset:

https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/power.html?cp=4_2_0_17_8_2#register.RESETREAS

https://infocenter.nordicsemi.com/topic/com.nordic.infocenter.nrf52832.ps.v1.1/power.html?cp=4_2_0_17_7#unique_832471788

[achraf]

awneil said:

Sounds like you have a power supply issue.

I think its the one, weird , even I'v used a DC - DC MP1584 It provides 3A output and I think its good enough.

awneil said:

Possibly also RF interference.

No because I'am using a simcom module, External from the Nrf52832 custom board .

awneil said:

You think you might be causing a Watchdog reset

no its not caused by the watchdog reset, because I made a code that it init the board : close the tcp shutdown the module, reconnect, configuration. so when its reset it will take a lot of time to do this init things and also it will be clear for me thats caused by a reset.

so due to our conversation , is it cause by the power, or what do you think about the crystal because its custom board as you know , or no ?
I appreciate your reply.

[awneil]

achraf said:

It provides 3A output and I think its good enough

What does the documentation for your GSM module tell you?

Again, the key thing here is that the current draw has very sharp spikes - the peak could well go over 3A!

So it's not just about being able to give a steady-state 3A - it's about being able to maintain regulation through a spike that hits 3A in a millisecond or less.

You need to get an oscilloscope on your supply rails to check that they're not drooping.

[achraf]

awneil said:

What does the documentation for your GSM module tell you?

it sim868 a 2A peak current 
is the power its the main one , so I could check that , what do you think about the crystal ? or any sdk configuration BLE priority.