nRF9160 DK PSM current too high after opening and closing a TCP socket

[Houwer de Geus]

Hi,

I tried the following AT settings on the nRF9160 DK board:

AT+CPSMS=1,,,"00111000","00011110"

AT+CFUN=1

After this the modem enters PSM mode and the current is about 6uA. So far so good.

When I do the same, but open a (valid) TCP socket and close the socket after the AT+CFUN=1 like:

sock = nrf_socket(NRF_AF_INET, NRF_SOCK_STREAM, NRF_IPPROTO_TCP)

nrf_connect(sock,...)

nrf_close( sock)

Then the following thing happens:

1) The floor current in PSM mode reaches 6uA

2) At a one second interval, the current increases to 14mA for a short time and falls back to 6uA. This leads to an average current of about 125uA.

What Can I do to stop the 1 second interval action during the PSM interval?

• We are using our own ide, using the supplied libraries of Nordic Semiconductor.
• bsd lib: v0.2.1
• trace interrupt enabled, Interrupt calls bsd_os_trace_irq_handler(), no trace printout
• The TCP connection is functional (open, send, recv...)

Best regards,

Houwer de Geus

[Sigurd]

Hi,

Thank you for the example. We have reproduced the issue with the unexpected 1s interval wakeups. We will fix this issue in a future release of the modem fw.

Best regards,

Sigurd

[Thomas]

Is this issue fixed in version 1.2 of the modem firmware? I'm seeing the same 1 second wake ups after closing the socket and powering down the modem (AT+CFUN=0).

[Sigurd]

Thomas said:

Is this issue fixed in version 1.2 of the modem firmware?

 Yes

Thomas said:

I'm seeing the same 1 second wake ups after closing the socket and powering down the modem (AT+CFUN=0).

This is most likely not related to the modem firmware then, but a thread used in your application code.

Please create a new case for your issue: https://devzone.nordicsemi.com/support/add

[Thomas]

That is doubtful as I can replicate it in a single thread, but I have made a new case anyway:

https://devzone.nordicsemi.com/f/nordic-q-a/63835/nrf9160-dk-sleep-current-too-high-after-opening-and-closing-a-tcp-socket