nRF9160 AT commands visible within modem trace backend RTT recordings

Question

Dear support team, 
 do the modem trace binaries contain the AT commands sent to/from the modem when trace backend RTT has been used instead of UART? Several month ago I used modem tracing with trace backend UART and all AT commands were visible within Wireshark but now with trace backend RTT the LTE and IP communications is visible but no AT commands are shown. We are using SDK 2.2 and modem firmware 1.3.6 on a custom board. It might also be a configuration issue on our site but first it would be good to know if in general the AT communication should be available with RTT trace backend. 
 Best regards, Peter

Didrik Rokhaug · Accepted Answer

Hi, 
 The modem sends out the same traces regardless of the trace backend. 
 The traces should also be decoded in the same way, so there shouldn't be an issue on that end either. 
 One thing that can cause differences between the different trace backends are their throughput, and how often they drop traces. Previously, the RTT backend used to be less stable than the UART backend. Though since then, there has been some improvements to the RTT backend, so I don't know how true that is anymore. 
 Another problem with the RTT backend is that it can be hard to get the beginning of the trace, so if that is where you send your AT commands, that might be the reason why. 
 Best regards, 
 Didrik

nRF9160 AT commands visible within modem trace backend RTT recordings

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