What is the latest RCP release is compatible with the otbr-posix v1.4?

[Mugunthan]

Issue:

The OTBR could run with RCP versions built with SDK v2.3.0 and v2.4.2 but couldn't work with fw from SDK v2.9.0. Hence, I wanted to know which of the latest SDKs works with the mentioned OTBR version. Also, if there is any kind of mapping table describing these compatibilities between OTBR and NCS SDK version, that would be appreciated.

Setup:

• Machine: Linux root 5.15.32-lts-next #1 SMP PREEMPT Tue Jun 7 02:34:46 UTC 2022 armv7l armv7l armv7l GNU/Linux
  
• otbr-posix: Built with ref https://github.com/nxp-imx/meta-nxp-connectivity/commit/a954b9fde9ac6941c457a76f7a5150cb3bfd284a
• HW: nrf52840
• Working RCP versions: SDK v2.3.0, v2.4.2
• Non-Working RCP versions: SDK v2.9.0

ot-ctl response - Working:

But when I tried to flash the RCP fw from SDK v2.9.0, the otbr wasn't able to bind with the RCP port, hence, ot-ctl couldn't run

otbr.log:

Please let me know if you need any information.

[Maria Gilje]

Hello,

I just took a quick look through the release notes for the minor nRF Connect releases between v2.4.2 and v2.9.0 and one possible reason for the new incompatibility is that a RCP feature set was introduced with v2.7.0 which is the default feature set for the RCP sample from that point on. Do you see any changes when switching out the CONFIG_OPENTHREAD_NORDIC_LIBRARY_RCP feature set with CONFIG_OPENTHREAD_NORDIC_LIBRARY_MASTER?

Best regards,

Maria