Long range and poor communication link

[Sebastien DRI]

Hi Folks,

I have a question regarding long range and an observed poor communication link with some packet lost.

Does the errata 191, linked here could provide an explanation to this phenomena?

Is the workaround described in this errata executed automatically inside softdevice or do we add it manually after softdevice is started? (we use the 7.0.1 version with SDK_16.0.0_98a08e2 )

My last question is about the compatibility matrix of the nrf52840 : Could you please confirm that the SoC version shall be rev D version 2 regarding the 7.0.1 softdevice version? Is there any issues in using the 7.0.1 version onto an older chip revision (A, B or C or D version 1) ?

Thank you in advance for your support.

The best.

[Kenneth]

Hello,

Errata 191 was included from S140 softdevice v6.0.0, from the release notes this is described as:
"Fixed an issue that could lead to high packet error rate when receiving on LE Coded PHY (DRGN-9793)."

It's automatically included yes.

An overview of nRF52840 revisions are found here:
https://infocenter.nordicsemi.com/topic/comp_matrix_nrf52840/COMP/nrf52840/nRF52840_ic_revision_overview.html

All the revision 3 have their own unique ordering number as described in the informational notice here:
https://infocenter.nordicsemi.com/pdf/in_141_v1.1.pdf 

"Customers who want to take advantage of the changes introduced in revision 3 will need to place orders via separate ordering codes (nRF52840-CKAA-F and nRF52840-QIAA-F). Production of revision 2 (build code Dx0) is maintained and can be ordered using the existing ordering codes (nRF52840-CKAA, nRF52840-QIAA). "

Could you please confirm that the SoC version shall be rev D version 2 regarding the 7.0.1 softdevice version?

I assume you mean Engineering D and revision 2 of the nRF52840. Looking at:
https://infocenter.nordicsemi.com/topic/comp_matrix_nrf52840/COMP/nrf52840/nRF52840_ic_rev_sdk_sd_comp_matrix.html 

I can confirm that revision 2 is compatible with v7.0.1 yes. The Engineering B, C and revision 1 have not been tested with v7.0.1.

My general comment on packet loss with coded phy:

The packets take 8x as long to transmit, so if you are testing in an environment with much interference from other WiFi or BT devices you may not get much range improvement due to high risk of collisions and interference due to the longer time on-air.

Kenneth

[Sebastien DRI]

Thank you for your answer.

Everything is clear now.