MQTT return ERROR after 24 hours

[RobertT]

Hello!

 I am sending MQTT commands over UART from an NRF52840 DK to the NRF9160 DK which has the ibasis sim card inside. I noticed 3 times so far that after 24 hours , 1 hour tolerance, I get only  ERROR messages returned after sending the MQTT commands with the payload.  Basically I need to reset the NRF52840 DK and  re-send all the MQTT commands for connecting to the MQTT broker, autenthificating, opening connection and initialising the modem ( AT+CFUN = 1 etc) .

 I was wondering if there were previous experiences like this.  I did use an osciloscope and the NRF52840 DK is sending the right commands with the good payload over UART even after 24 hours, it's just like the modem closes the connection or something...

All the best,

Robert.

[Carl Richard]

Hi again!

This sample writes the logs over the RTT protocol. So if you connect to the device with the JLink RTT Viewer (or using the built in terminal in SES), the logs should be printed there.

Logs are not to be confused with a modem trace, which only can be read by us here. I don't need a modem trace from you yet, as I don't believe that this is a modem issue.

Best regards,
Carl Richard

[RobertT]

Yes, I did confuse the 2 of them. Will get on it and get back to you. All the best!

[RobertT]

An update + unknown:

 - after 3 days of working the modem stoped again transmitting over MQTT; connected the oscilloscope probe to the UART and got nothing back this time, no "ERROR" message or anything else. The NRF52840 was transmitting data to the NRF9160 continuously though. 

 I pressed " RESET" on the NRF52840 DK and it had no effect on the NRF9160 DK, still no reply on UART ...like an " OK " back from the at commands or an " ERROR " ; I pressed " RESET"  on the NRF9160 DK and I got the " READY" reply message and it started working again as expected with all the reply messages on UART.

- I started the RTT Viewer V6.98b on Windows and will get back with the logs when the modem stops next time. 

  All the best,

Robert.

[Carl Richard]

Thanks for the update. The nRF9160 must have crashed somehow, which is unfortunate. Hopefully the logs will provide some insight!

Best regards,
Carl Richard

[RobertT]

Hello, Richard!

 I attached 2 log files, data and terminal logging. 

The NRF9160DK stoped again without any reply on the UART channel, while the NRF52840 was sending data every 20 seconds as it should. I pushed " RESET " on the NRF9160DK and started working again.

 The NRF9160 DK USB is connected to the PC and the NRF52840 DK is connected to an USB mains adapter. The time when it worked for 3 days they were both connected to the mains through an USB adapter. The PC is set to never go to sleep so I do have power all the time. Doesn't make sense to mention this setup  but I though to add it in also...

 I started LOGGING after I connected to the NRF9160DK. If the logs are not the proper ones please let me know.

All the best,

Robert.

=====added by me manually because I started loging after I turned ON the RTT Viewer===

=====START HERE====
LOG: J-Link RTT Viewer V6.98b: Logging started.
LOG: Terminal 0 added.
LOG: Terminal 10 added.
LOG: Connecting to J-Link via USB...
LOG: Device "NRF9160_XXAA" selected.
LOG: ConfigTargetSettings() start
LOG: ---Setting ROM table---
LOG: ConfigTargetSettings() end
LOG: Found SW-DP with ID 0x6BA02477
LOG: DPIDR: 0x6BA02477
LOG: Scanning AP map to find all available APs
LOG: AP[7]: Stopped AP scan as end of AP map has been reached
LOG: AP[0]: AHB-AP (IDR: 0x84770001)
LOG: AP[1]: AHB-AP (IDR: 0x24770011)
LOG: AP[2]: JTAG-AP (IDR: 0x12880000)
LOG: AP[3]: APB-AP (IDR: 0x54770002)
LOG: AP[4]: JTAG-AP (IDR: 0x12880000)
LOG: AP[5]: JTAG-AP (IDR: 0x12880000)
LOG: AP[6]: MEM-AP (IDR: 0x128800A1)
LOG: Iterating through AP map to find AHB-AP to use
LOG: AP[0]: Core found
LOG: AP[0]: AHB-AP ROM base: 0xE00FF000
LOG: CPUID register: 0x410FD212. Implementer code: 0x41 (ARM)
LOG: Found Cortex-M33 r0p2, Little endian.
LOG: FPUnit: 8 code (BP) slots and 0 literal slots
LOG: Security extension: implemented
LOG: Secure debug: enabled
LOG: CoreSight components:
LOG: ROMTbl[0] @ E00FF000
LOG: ROMTbl[0][0]: E000E000, CID: B105900D, PID: 000BBD21 Cortex-M33
LOG: ROMTbl[0][1]: E0001000, CID: B105900D, PID: 000BBD21 DWT
LOG: ROMTbl[0][2]: E0002000, CID: B105900D, PID: 000BBD21 FPB
LOG: ROMTbl[0][3]: E0000000, CID: B105900D, PID: 000BBD21 ITM
LOG: ROMTbl[0][5]: E0041000, CID: B105900D, PID: 002BBD21 ETM
LOG: ROMTbl[0][6]: E0042000, CID: B105900D, PID: 000BBD21 CSS600-CTI
LOG: RTT Viewer connected.
LOG: Terminal logging started.
LOG: Data logging started.
=====END HERE======

=====WHAT IS BELLLOW IS ALL THAT THE SYSTEM SAID AFTERWARDS====

# SEGGER J-Link RTT Viewer V6.98b Data Log File
# Compiled: 15:05:00 on Mar 12 2021
# Logging started @ 10 Apr 2021 22:18:33

logsRTT3.log