NRF52840 won't receive from some TI CC2538 chips

[Libertas]

I have two devices on TI CC2538 that having problems talking to the NRF52840 dongle.

1. The channel is channel 11
2. There are 8 devices using TI CC2538. Only two of them are having problems
3. NRF52840 dongle ABSOLUTELY cannot see any packet from those two devices
4. I tried three dongles. It is consistent.
5. I doubted my own firmware. So I downloaded the NRF52840 sniffer and tried Wireshark. Same result! Those two devices disappeared in thin air from the dongle!
6. TI CC2538 can see packets from all devices, regardless of TI or Nordic.
7. TI CC2530 sniffer can see the packets from those two devices just fine.
8. Signal strength is not a problem. I have readings of -63dBM and -70dBM from Hub and the devices are much closer to the NRF53840 dongle.

I can only think of some compatibility problem. I don't think it has anything to do with software at this point.

I have a feeling that this is serious and we need to find out why?

I can give you guys the devices for further analysis.

[Susheel Nuguru]

We go through the interoperability tests during the Thread certification, so it should have been ok when communicating with other Vendor thread devices if they have done the same. Also we recommend you to use the nRF Connect SDK instead of the nRF5SDK. nRF5 based SDK are old and are in maintenance mode only. All new features and fixes will be coming the nRF Connect SDK only. 

[Libertas]

First of all, Thread is based on 802.15.4, and I am discussing 802.15.4 reception on nRF52840.

Secondly, I didn't have reception problems with ALL my devices based on TI CC2538. Out of 9 devices, there are only two devices that have the problem.

Thirdly, I am using the official Nordic sniffer firmware (for 802.15.4) which I downloaded from your GitHub page:

https://github.com/NordicSemiconductor/nRF-Sniffer-for-802.15.4

It is obvious that if it cannot receive, it cannot communicate.

I am planning to test more devices on my side. In the meantime, if you have an updated version of the sniffer firmware I would like to try and test again.

[Susheel Nuguru]

Libertas said:

First of all, Thread is based on 802.15.4, and I am discussing 802.15.4 reception on nRF52840.

I understand that, but there are two Thread solutions from us, 

1. Thread solution based on old nRF5SDK which I am guessing is the one you are using.
2. 'Thread solution based on our latest nRF Connect SDK.

The one you are using seems to be on the older SDK which are in frozen now and no new development happens on that SDK. We recommend you to use the latest version of NCS.

[Libertas]

I am not developing Thread. I am developing another mesh protocol that we are going to open source.

That's why I am testing plain 802.15.4 reception with Nordic sniffer firmware. And it couldn't receive from 2 out of 9 devices.

[Susheel Nuguru]

I see, thanks for making the crystal clear. If you are developing another mesh protocol which is not one of our solutions, then I do not think I can help you much here. Our hardware is proven to be 802.15.4 capable and we have protocols that work on it. It is not possible for us to validate the timing and other implementation details of protocols that are not our solution.

[Libertas]

I have invested a lot of effort in the nRF solutions. And I am baffled by the symptoms I experienced.

Let me rephrase the question a little bit.

The nRF52840 802.15.4 sniffer firmware, which is 4 years old, won't receive 802.15.4 packets from some devices. Is there any updated version of the firmware?

I do hope it is due to something I did wrong on my side as I am still feeling surreal about it.

[Susheel Nuguru]

Libertas said:

The nRF52840 802.15.4 sniffer firmware, which is 4 years old, won't receive 802.15.4 packets from some devices. Is there any updated version of the firmware?

Not that I know of. I have But I have asked the internal team to see if there are any unpublished updates on this but I have not received any answer yet. Most likely there are no updates to the sniffer tool you are using. There does not seems to be any active development ongoing on this sniffer tool.