nRF9160 SLM behaviour

[isurki]

Good morning,

I am using the nRF9160 as an AT command modem running the SLM app. I aim to set eDRX and disable PSM (PSM doesn´t make sense in our project). According to the modem response and the current consumption measured with the Power Profiler, the eDRX mode is correctly enabled:

AT+CEDRXS=1,5,"0011"

--> OK

AT%XPTW=5,"0001"

--> OK

AT+CEDRXRDP

--> +CEDRXRDP: 5,"0011","0011","0001"

I have more doubts about PSM:

AT+CPSMS=0

--> OK

AT+CPSMS?

--> +CPSMS: 0

Although it seems to be disabled, I am still getting these values in response to AT%XMONITOR:

%XMONITOR: 5,"vodafone ES","vodafone ES","21401","060C",9,20,"0F464F3E",49,6253,79,46,"0011","11100000","00000110","01001001"

Besides, the current consumption from Power Profiler shows a behaviour I can not explain, with a current consumption of about 30 mA and ∼ 20 seconds every 5 minutes exactly. If PSM is disabled what is the source of the current consumptions shown in red in the picture?

[Maria Gilje]

Hello,

Do you have a modem trace of this situation? Also, which Modem FW version are you using?

Best regards,

Maria

[isurki]

Hi,

I don't have modem trace enabled as the hardware is a custom board and we are using UART0 to communicate with the main MCU of the board. Is the modem trace necessary for you? Could we use the JTAG port to enable modem trace? The modem firmware version is 2.6.1-lte-11b6ed4846a8. 

Regards,

Ander.

[Maria Gilje]

Hey Ander, 

Besides, the current consumption from Power Profiler shows a behaviour I can not explain, with a current consumption of about 30 mA and ∼ 20 seconds every 5 minutes exactly. If PSM is disabled what is the source of the current consumptions shown in red in the picture?

I wonder if the periodic high consumption can be the device doing a periodic search. With AT%PERIODICSEARCHCONF, periodic searches during limited service can be configured. In the linked documentation there are some examples for ultra low power configurations.

isurki said:

The modem firmware version is 2.6.1-lte-11b6ed4846a8. 

This seems to be the nRF Connect SDK version. I was thinking about the firmware binaries with a name on the form mfw_nrf9160_x.x.x.zip which are provided as downloads here. I may be missing some information, so feel free to enlighten me.

isurki said:

Could we use the JTAG port to enable modem trace?

You can use RTT as a backend for modem trace, but it is an experimental feature and it requires a debugger (either dedicated or a DK with an onboard debuger). It is also possible to create custom backends.

isurki said:

Is the modem trace necessary for you?

Not at this point. I'll let you know if I find we need one.

Best regards,

Maria