Serial LTE Modem - IP, UDP, GPS, SLEEP commands documentation

RE: Serial LTE Modem - IP, UDP, GPS, SLEEP commands documentation

Håkon Alseth — Tue, 10 Mar 2020 11:49:21 GMT

Hi,

[quote user="michalm"]AT#XSLMVER[/quote]

This gives the version of the serial_lte_modem, which is v1.2 in the time of writing:

https://github.com/NordicPlayground/fw-nrfconnect-nrf/blob/master/samples/nrf9160/serial_lte_modem/src/slm_at_host.c#L32

[quote user="michalm"]I can not find there also nothing about AT#XPING=<addr>,<length>,<timeout>[,<count>[,<interval>]] and I am no table to make it working, since e.g. AT#XPING="192.168.0.1",100,10 returns just ERROR (I am using APN where 192.168.0.0/16 is valid target).[/quote]

My apologies, but this isn't very well documented yet. The best option for now is to read the code to see how it should behave: https://github.com/NordicPlayground/fw-nrfconnect-nrf/blob/master/samples/nrf9160/serial_lte_modem/src/slm_at_icmp.c#L348

the timeout is in ms, so I would recommend that you try to expand it to see if this has any impact. 192.168.0.1 -> is this the gw? if not : are you certain that the route in your gateway setup allows ICMP, or that the fw doesn't drop it?

[quote user="michalm"]I found sockets operation options and socket types in implementation, but it is confusing to request socket type 2 (UDP) and get response with socket type 17 :-([/quote]

17 is from this enum:

https://github.com/NordicPlayground/fw-nrfconnect-zephyr/blob/master/include/net/net_ip.h#L62

I'm not sure where you get 2 from? The nrf_socket.h defines NRF_IPPROTO_UDP as 2, but this is translated to IPPROTO_UDP in this file: https://github.com/NordicPlayground/fw-nrfconnect-nrf/blob/master/lib/bsdlib/nrf91_sockets.c#L303

You shouldn't see a translation like this in the application space.

[quote user="michalm"]UDP data sending is delayed ~4s, any hit why please ?[/quote]

Are you using the latest master branch?

[quote user="michalm"]Can not find also how to send binary data by AT#XUDPSENDTO=<url>,<port>,<data>. I am able to use it with ascii strings.[/quote]

Yes, that is currently a restriction. I'll forward this to the developers.

[quote user="michalm"]How many UDP packets are stored in buffer before executing AT#XUDPRECVFROM please ?[/quote]

This depends on the overall size of the packets and how many you have received, but the limits are in general described in the bsdlib limits file: https://github.com/NordicPlayground/nrfxlib/blob/master/bsdlib/include/bsd_limits.h

Kind regards,

Håkon

RE: Serial LTE Modem - IP, UDP, GPS, SLEEP commands documentation

Michal Mühlpachr — Fri, 06 Mar 2020 15:30:07 GMT

Thank you,

I am still not able to find anything about:

AT#XSLMVER
AT#XSLEEP[=<shutdown_mode>]
AT#XCLAC

I can not find there also nothing about AT#XPING=<addr>,<length>,<timeout>[,<count>[,<interval>]] and I am no table to make it working, since e.g. AT#XPING="192.168.0.1",100,10 returns just ERROR (I am using APN where 192.168.0.0/16 is valid target).

Can not find also how to send binary data by AT#XUDPSENDTO=<url>,<port>,<data>. I am able to use it with ascii strings.

I found sockets operation options and socket types in implementation, but it is confusing to request socket type 2 (UDP) and get response with socket type 17 :-(

UDP data sending is delayed ~4s, any hit why please ?

How many UDP packets are stored in buffer before executing AT#XUDPRECVFROM please ?

Any examples would be extremely helpful.

Would you be so kind and hint please ?

Thank you.

RE: Serial LTE Modem - IP, UDP, GPS, SLEEP commands documentation

Håkon Alseth — Fri, 06 Mar 2020 14:23:08 GMT

Hi,

The IP and GNSS parts are provided by bsdlib, which is documented here:

http://developer.nordicsemi.com/nRF_Connect_SDK/doc/1.2.0/nrfxlib/bsdlib/README.html#

As for the AT commands that are non-IP and non-GNSS related, they are in the AT commands, which you link to.

You can choose if you want to control it from a normal UART session on the PC side, or via a client application for nRF5 device, which can be found here: https://github.com/NordicPlayground/nrf5_clients_for_nrf91_network_service

Kind regards,

Håkon