LTE-M always connected

RE: LTE-M always connected

Heidi — Thu, 17 Jun 2021 15:03:02 GMT

Can the low power mode affect re-connection to our TCP server or switching TCP servers?

No, having PSM enabled should not affect this.

Can I switch freely between low power mode in battery operation just when I upload data to our AppServer?

Yes, you can enable and disable PSM mode freely.

RE: LTE-M always connected

DavidKaplan — Thu, 17 Jun 2021 12:13:53 GMT

Shalom!

You are correct. I don't know how I missed that I called my wrapper function ami_main_switch_low_power()

with its parameter true! When the device will run on batteries I will want this and sleep most of the time, but with external power they want a continuous connection so that web queries can arrive.

I will add the AT+CPSMS? command before connecting so I can see the power saving mode on the debug channel.

I will need to test everything again with no low power next Sunday as this is the end of my work week.

Can the low power mode affect affect re-connection to our TCP server or switching TCP servers?

Can I switch freely between low power mode in battery operation just when I upload data to our AppServer?

Thanks and I will get back with the results hopefully early next week.

RE: LTE-M always connected

Heidi — Thu, 17 Jun 2021 11:57:25 GMT

From your application, it looks like you're calling lte_lc_psm_req(true), which you can't do if you want the device to stay in RRC Connected mode all the time.

[quote user="DavidKaplan"]when testing always our connected work mode[/quote]

Does this mean you fixed the issue?

Please try sending AT+CPSMS after start-up to see if PSM is enabled.

RE: LTE-M always connected

DavidKaplan — Thu, 17 Jun 2021 04:14:41 GMT

Shalom!

This morning I wanted to duplicate the problem and create a debug log. I may have added late afternoon a code segment that when a send() returns an error, I understand that there is a problem and close the socket.

In the debug below you can see that after the modem registers and connects to the cellular network, I issue a series of AT commands primarily to get information for our GetStatus() command and then try to connect to our TCP server. After connection I restarted my TCP Server and then try to reconenct.

I added to the debug [?!?] explanations. Previously when I tried in my Nordic code to close the current TCP server connection and then connect to another server I got the errno 116 always and immediately. Yesterday after I stopped the TCP server and restarted it I got a 1116 also the first reconnection try.

Thanks David

devzone.nordicsemi.com/.../AMI_5F00_debug_5F00_17Jun2021a.txt

RE: LTE-M always connected

DavidKaplan — Thu, 17 Jun 2021 03:20:26 GMT

Shalom!

We will use the GPS in one software version, so I was testing it, without success, maybe because of obstructions, but in any case the define is remarked in the proj.cong file when testing always our connected work mode. I will attached our main with irrelevant functions deleted and again my ami_socket.c TCP code.

Thanks David

devzone.nordicsemi.com/.../2072.prj.conf devzone.nordicsemi.com/.../ami_5F00_main.c devzone.nordicsemi.com/.../ami_5F00_socket.c

RE: LTE-M always connected

Heidi — Wed, 16 Jun 2021 13:04:53 GMT

Hi!

Can I see your main.c and Kconfig file as well, to understand what the configurations do?

I see

CONFIG_GPS_CONTROL_PSM_ENABLE_ON_START

is enabled which could mean you are still enabling PSM on startup.

You can try sending AT+CPSMS after start-up to see if PSM is enabled.

Best regards,
Heidi

RE: LTE-M always connected

DavidKaplan — Thu, 10 Jun 2021 03:42:59 GMT

devzone.nordicsemi.com/.../trace_2D00_2021_2D00_06_2D00_10T03_2D00_19_2D00_46.258Z_5F00_CONFIG_5F00_PM_5F00_DEVICE_3D00_y.bin devzone.nordicsemi.com/.../trace_2D00_2021_2D00_06_2D00_10T03_2D00_26_2D00_57.987Z_5F00_CONFIG_5F00_PM_5F00_DEVICE_3D00_n.bin

Shalom!

devzone.nordicsemi.com/.../0167.prj.conf

Shalom!

I took two traces, one with CONFIG_PM_DEVICE=y and the other CONFIG_PM_DEVICE=n.

The modem connects to the cellular network and then my application connects by TCP to my Application server and after a few seconds of inactivity the modem goes to RRC Idle.

I also attached my proj.cdevzone.nordicsemi.com/.../0181.nrf9160dk_5F00_nrf9160ns.overlayonf file. Our custom nRF9160 board contains a AT24C512 EEPROM, a LSM6DSL acceleration chip, a SI7055 temperature chip and a mx25r6435 external flash.

I created an overlay just in preparation for the board's arrival adding the chips to existing buses but when the config are enabled I get compile errors. Evidently I am doing something wrong or missing something in my overlay.

Thanks

David

RE: LTE-M always connected

Heidi — Wed, 09 Jun 2021 15:01:44 GMT

Hi! Apologies for the late reply.

Could you please take a modem trace when this is happening so we can have a closer look?

See Collecting a modem trace for the nRF9160 DK

Best regards,

Heidi

RE: LTE-M always connected

DavidKaplan — Mon, 07 Jun 2021 10:14:15 GMT

Could someone help me on this?