MCU was reset from time to time

[mark.zhang]

HI,

I have a product which scan for RFID card through NFC and Mobile Device through BLE after nRF52840 MCU was wakeup.

If I scan NFC and BLE scanning separately, everything was OK.

But, If I start BLE scanning first, do connect-discovery-exchange data in the event handle, then in a loop, I scan NFC for RFID card and check BLE state, nRF52840 will be reset from time to time.

May I scan NFC and BLE at same time, if yes, how to do it ?

Thanks,

Mark,

[Charlie]

Hi Mark,

Could you provide more informaiton about your program?

Like which SDK are you using, nRF5 SDK or NCS? which specific version?

It would be great if you can share a minimal sample that can reproduce this issue.

Best regards,

Charlie

[mark.zhang]

HI, Charlie:

  I use ncs v2.3.0

 I used below loop to scan MobileID with BLE and RFID card with NFC:

scanStart();
while(1) {
if(gBleState == Ble_Nothing) {
gBleSequence = 1;
bMobileIDReady = false;
scanStart();
}

if((scanCard() > 0) || (bMobileIDReady == true)) {
if(gBleState == Ble_Scanning) {
scanStop();
} else if((gBleState == Ble_Connected) || (gBleState == Ble_Discoveried)) {
disconnect_from_mobile();
}

Delay_ms(100);
ConfirmationBeep();

if(gBleState == Ble_Completed) gBleState = Ble_Nothing;
}

During scan MobileID with BLE, I used as Central from the sample central_uart.

Mark,

[Charlie]

Hi Mark,

I have following suggests to help you debug this issue: 

1) Try to enable log and check the debug output from terminal, set "CONFIG_RESET_ON_FATAL_ERROR=n" to see the error cause when failure happens.

2) Try to set up a seperate Thread for NFC opetation since you have verifed they can work seperately. I feel not confident about the bloking logic in your while loop.  

Best regards,

Charlie 

[mark.zhang]

HI, Charlie: 

My project is a bare-metal firmware, should I convert the project to RTOS before I can use separate thread for BLE scanning ?  If yes, is that hard to convert from bare-metal to RTOS ? I'm a beginner on RTOS.

Thanks,

mark,

[Charlie]

Hi Mark,

This is not hard since your porject is based on NCS/Zephyr.

Just learn about Thread usage and refer to the Zephyr sample. We also have DevAcademy course cover Zephyr RTOS basics.

https://academy.nordicsemi.com/courses/nrf-connect-sdk-fundamentals/lessons/lesson-7-multithreaded-applications/topic/scheduler/

https://docs.nordicsemi.com/bundle/ncs-latest/page/zephyr/kernel/services/threads/index.html

• Basic SynchronizationManipulate basic kernel synchronization primitives.
• Basic thread manipulationSpawn multiple threads that blink LEDs and print information to the console.
• Dining PhilosophersImplement a solution to the Dining Philosophers problem using Zephyr kernel services.
• Dumb HTTP server (multi-threaded)Implement a simple HTTP server supporting simultaneous connections using BSD sockets.

Best regards,

Charlie