Downwards compatibility for nRF9160 modem firmware version 1.3.6

[Martin N]

The documentation about the downwards compatibility for nRF9160 modem firmware version 1.3.6 states that only nRF Connect SDK versions 2.2.0 & 2.5.1 are supported.

See https://infocenter.nordicsemi.com/topic/comp_matrix_nrf9160/COMP/nrf9160/nrf9160_modem_fw.html

Is this a documentation flaw or has support for SDK versions like 2.4.x & 2.5.0 really been dropped?

Martin

[Elfving]

Sorry about being unclear Saran,

What I meant to say was that this should be done within the day, 20days ago. And I thought it was.

I'm looking into what has been done here, but I assume that Martin Nelisse is saying is true, that they've only updated this on the docs.nordicsemi page. 

Martin N said:

This shows SDK 2.2.0 & 2.3.0 & 2.4.2 and 2.5.1 are compatible with modem firmware 1.3.6. However the newly released SDK 2.5.2 is nowhere in this compatability list! Which modem firmwares are compatible with SDK 2.5.2?

So what we are listing now are only what has been "production-tested", so it can be also somewhat be considered a formality. I've now checked internally that MFW 1.3.6 is expected to be compatible with NCS 2.5.2, though unfortunately this has also not been updated on the website yet. 

Regards,

Elfving

___ UPDATE: ___

I've confirmed that they are only updating our new page for documentation from now on: docs.nordicsemi.com. Infocenter got its last update in January. For all new information, please use docs.nordicsemi.com.

[SaranSiriwa]

Thanks for the update, Is SDK 2.4.0 in the list to be tested?

If so, could you please let me know when it will be tested?

Saran

[Elfving]

I am not sure it necessarily will.

I could check, though I would either way recommend switching to the 2.4.2, as it would be a version with some more patches enabled. Switching from 2.4.0 should go rather smoothly as well. Is there any particular reason why you are not using 2.4.2?

Regards,

Elfving

[SaranSiriwa]

My system was tested with version 2.4.0 and changing to 2.4.2 requires regression testing.

1. Please let me know after you have checked.

2. The latest SDK of 2.4.X is 2.4.3, why is 2.4.3 not tested but 2.4.2 was tested instead?

[Elfving]

So 2.4.0 will not be tested unfortunately.

For 2.4.2 and mfw 1.3.6 we have done extensive testing. Because of the similarities, it was not worth the overhead for us to apply all the same tests to 2.4.1 and 2.4.0. We hope that you can either port you application to 2.4.2, or, if you check that your applications works as expected, just go ahead and use 2.4.0. There are very few differences between these versions, which would make it likely to go smoothly to either simply upgrade to NCS2.4.2, or use NCS2.4.0 with MFW1.3.6. As 

So one reason why we choose to test the versions we do, is to make sure that there is a supported and tested "FOTA path" to continuously upgrade NCS and MFW versions into a newer one. Another reason is that the versions we choose might be especially supported in some other fashion. LWM2M carrier (certification in Verizon network) is for instance supported in NCS 2.4.2. 

I guess this doesn't really change anything regarding the need for testing, but there aren't that many changes made to NCS between these versions. This is between 2.4.1 and 2.4.2:

$ git log v2.4.1..v2.4.2 --oneline
75adfe8909f (tag: v2.4.2) manifest: NCS 2.4.2
281f8860fa1 version: Update VERSION to 2.4.2
a68bf28300b treewide: bump MCUboot image version in projects with Thingy:53 support
9308bed911b doc: releases: LwM2M change log
6da41a001a1 samples: lwm2m_client: Server initiated bootstrap fix
df7b13fef27 doc: update doc for 2.4.2
b9ba6d11c71 samples: lwm2m_client: Client state machine fix
eeaa55cc3c3 manifest: update homekit revision
b5ae94fac49 manifest: nrf_modem v2.4.1

Either way, I am sorry about this. Have a good week-end.

Regards,

Elfving