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

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

Thomas — Thu, 16 Jul 2020 05:52:05 GMT

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

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

Sigurd — Wed, 15 Jul 2020 08:36:38 GMT

[quote user="Thomas2197"]Is this issue fixed in version 1.2 of the modem firmware?[/quote]

Yes

[quote user="Thomas2197"]I'm seeing the same 1 second wake ups after closing the socket and powering down the modem (AT+CFUN=0).[/quote]

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

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

Thomas — Wed, 15 Jul 2020 05:26:53 GMT

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).

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

Sigurd — Tue, 09 Apr 2019 13:31:09 GMT

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

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

Houwer de Geus — Mon, 08 Apr 2019 14:43:38 GMT

Hi Sigurd,

Hereby I send you the example. The order is:

AT+CPSMS=1,,,"00111000","00011110"
AT+CFUN=1
Wait for registration using the iBasis SIM. It indicates roaming
Open TCP socket: socket_fd = nrf_socket(NRF_AF_INET, NRF_SOCK_STREAM, NRF_IPPROTO_TCP);
use nrf_getaddrinfo() to retrieve the IP adress.

Perform TCP connect: nrf_connect(socket_fd, &ipv4Address, sizeof(nrf_sockaddr_in_t))

Close the Socket: ret = nrf_close(pContext->socket_fd);
And wait until PSM mode is activated after about 60 seconds active time.

devzone.nordicsemi.com/.../nRF91NordicExample.zip

Best Regards,

Houwer de Geus

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

Houwer de Geus — Mon, 08 Apr 2019 13:19:18 GMT

Hi Sigurd,

1) I will prepare this example. This will take some time. I will inform you when ready

2) No, with UDP I see the same 74 seconds active time (average current about 3mA) followed by PSM mode of 6uA. One time I did see the 125uA active current for a few seconds after active time, but it ended in PSM mode with 6uA active current.

3) With AT+CPSMS? I get the same values as requested (after registration succeeded, before opening the socket):

+CPSMS: 1,,,"00111000","00011110"

4) With AT+CGMR I get:

mfw-m1_nrf9160_0.6.8-30.alpha

I checked TCP again and I noticed once that the PSM mode was reached after 30 minutes, but most of the time it did not get into PSM mode.

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

Sigurd — Mon, 08 Apr 2019 08:19:11 GMT

Hi,

[quote userid="78529" url="~/f/nordic-q-a/45544/nrf9160-dk-psm-current-too-high-after-opening-and-closing-a-tcp-socket/180519"]It looks like the device is polling every second for something. Can you tell me what happens during the polling?[/quote]

This is the TCP stack, it's waking up every second.From your description it seems like the socket it not closed properly.

1) Could you provide a minimal working example that shows the issue ?

2) Do you see the same issue if you test with UDP ?

3) Could you check the PSM/DRX status when this happens ? (AT+CPSMS?)

4) What version of the modem fw are you using ?

5) Could you check the return code from the close function?

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

Houwer de Geus — Fri, 05 Apr 2019 13:27:01 GMT

Hi,

To be more specific, the T3324 active timer is set to 60 seconds, the T3412 timer is set to 24 hours. After performing AT+CFUN=1, the device enters PSM mode (6uA) after 74 seconds, so slightly more than the 60 seconds active time. This is ok.

After performing AT+CFUN=1 and opening a valid TCP socket (valid URL,port) and after closing that port without exchanging data, the device enters a state after 74 seconds in which it draws an average current of 580uA. 51 seconds later the average current drops to 125uA average, see my picture. So I waited even longer, about 30 minutes and the average current remains the same 125uA. It does not enter PSM mode with the expected 6uA. So my conclusion is, that I never reach the PSM mode.

So a single TCP open and close is enough to NOT enter PSM mode.It looks like the device is polling every second for something. Can you tell me what happens during the polling? And how I can reach PSM mode without polling?

Best regards,

Houwer de Geus

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

Sigurd — Wed, 03 Apr 2019 15:03:37 GMT

Hi,

[quote userid="78529" url="~/f/nordic-q-a/45544/nrf9160-dk-psm-current-too-high-after-opening-and-closing-a-tcp-socket"]At a one second interval, the current increases to 14mA for a short time and falls back to 6uA. [/quote]

I think it could be the idle time after the PSM TAU you are seeing. Before entering PSM, the device will be in idle mode DRX for a short while. See the images here, here and here: