nRF9160 SLM add PPP

RE: nRF9160 SLM add PPP

Zoptune — Mon, 09 Jan 2023 17:21:54 GMT

Hi and thanks for your answer,

I will go with the third option which is doing all the work on the ESP32 and use existing SLM AT commands.

It will require some work but I am much more comfortable with Espressif environment.

Thanks for your help :)

RE: nRF9160 SLM add PPP

Didrik Rokhaug — Mon, 09 Jan 2023 16:01:49 GMT

[quote user="AlexandreC"]It seems that the configured UART is exclusive to the PPP interface and that it cannot be used like I wanted to which is "shared" with the SLM by adding an SLM_PPP_MODE in addition to SLM_AT_COMMAND_MODE, SLM_DATA_MODE.[/quote]

The easiest solution will be to just use 2 UARTs. You could potentially use a switch to direct the UART signals, and that way only use one UART on the ESP32.

Another possibility would be create a new "UART driver" on the nRF9160, which reads the UART traffic, checks if it is an AT command or PPP command, and sends it to the right handler from there. I don't think it will be easy to express that in the device tree, but if you re-write the PPP code and SLM code to not use the device tree macroes to the the "UART device", I think it is doable.

A third option, is to use the HTTP, MQTT, etc. commands in the SLM, and not use PPP at all. It will let you avoid having to deal with the FW on the nRF9160, but might require more work on the ESP32 (depending on how much code you already have there)

RE: nRF9160 SLM add PPP

Zoptune — Sun, 08 Jan 2023 15:56:41 GMT

Hi Didrik Rokhaug and happy new year,

I investigated the code and how PPP works in the MoSH example and from what I understood it is not possible to use a single UART for the SLM and the PPP interface.

It seems that the configured UART is exclusive to the PPP interface and that it cannot be used like I wanted to which is "shared" with the SLM by adding an SLM_PPP_MODE in addition to SLM_AT_COMMAND_MODE, SLM_DATA_MODE.

I hoped that I could enable the PPP interface by adding a function like enter_pppmode() in the slm_at_host.c file.

If you have any information or advice about that that would be awesome.

Regards.

RE: nRF9160 SLM add PPP

Zoptune — Thu, 29 Dec 2022 10:27:51 GMT

Hi and thanks for your response.

Ok I will give it a try.

I will only use one UART as I only have one available and I will add a new mode in addition to SLM_AT_COMMAND_MODE, SLM_DATA_MODE and SLM_DFU_MODE.

If I end up with something satisfying enough I will push a PR 🙂

Regards and happy end of the year.

RE: nRF9160 SLM add PPP

Didrik Rokhaug — Wed, 28 Dec 2022 11:12:29 GMT

Hi,

I am not very familiar with PPP, but yes, I believe it will work. You might have to use a second UART for PPP, similar to what the MoSH does.

You might also be able to simply use the MoSH sample directly, though I haven't looked at the current consumption of the MoSH sample. It might end up being higher than the SLM where you have the #XSLEEP command.

Best regards,

Didrik

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