Hi,
I am facing a strange NB-IoT connectivity issue with the nRF9160 in Dammam, Saudi Arabia.
Setup
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SDK version: v2.5.0
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Toolchain: nRF Connect for SDK VSCode Extension
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Modem: nRF9160
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SIM type: NB-IoT SIM
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Hardware:
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Custom board using nRF9160
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Also tested with nRF9160DK for comparison
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Application/Test Used
I tested using the Nordic Developer Academy examples from:
Nordic Developer Academy - cell-fund examples
Specifically:
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Exercise 3
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Exercise 7
Observed Behavior
The setup works properly in Jeddah.
However, in Dammam the connectivity behavior is highly inconsistent:
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Some days it connects within seconds
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Some days it takes up to 1.5 minutes
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Some days it does not connect at all - stays in searching
I also tested the exact same code on the nRF9160DK and observed the same behavior, so it does not appear to be related to the custom hardware.
Additional Information
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SIM is configured for NB-IoT
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Tested both:
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LTE preference = Auto
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LTE preference = NB-IoT only
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Same behavior in both scenarios
Questions
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Has anyone seen similar regional/operator-specific NB-IoT behavior in Dammam?
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Are there recommended modem/network settings for unstable NB-IoT connectivity?
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Would modem trace logs help identify whether this is network attach related, coverage related, or operator related?
Additionally, it would be very helpful if someone could explain:
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How to enable modem trace output on UART0
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How to connect/use it with Cellular Monitor
Thanks.