boards: support new controller hardware rock5bplus

[ljm0451]

support Radxa's rock5b+:

1. boards/radxa/*: Board configuration files i. icm20602:/dev/spidev0.0 ii. ELRS:/dev/ttyS3
2. posix-configs/radxa/rock5bplus.config: Board starup file.

HOW TO BUILD AND INSTALL: see README.md

[ruiqurm]

Hi, thanks a lot for your contribution!

Currently, we have another PR doing similar work (see #3). To avoid duplicated efforts, could you consider adding support for other sensors, such as GPS, magnetometer, or ADC (for battery information reading)?

Since the other PR is more comprehensive, I’ll try to merge the two PRs together. Your additional contributions will be very helpful and appreciated!

[ljm0451]

Hi, thanks a lot for your contribution!

Currently, we have another PR doing similar work (see #3). To avoid duplicated efforts, could you consider adding support for other sensors, such as GPS, magnetometer, or ADC (for battery information reading)?

Since the other PR is more comprehensive, I’ll try to merge the two PRs together. Your additional contributions will be very helpful and appreciated!

Hi, thank you for the update and for considering the merging of our efforts! I'm happy to continue adapting the code and extend the support to include additional sensors such as GPS. I look forward to collaborating further and integrating these features into our comprehensive solution.

[Ncerzzk]

I'm curious about that elrs receiver can work in linux without any changes?

[ljm0451]

I'm curious about that elrs receiver can work in linux without any changes?

Hi, thanks for your feedback!

At this stage, I only tested it by running rc_input start -d /dev/ttyS3 without any error, and confirmed with rc_input status that there were no obvious issues.

I understand this is not a complete validation. I’ll continue to study and explore proper testing methods to ensure everything works correctly.

Thanks again!

[Ncerzzk]

I'm curious about that elrs receiver can work in linux without any changes?

Hi, thanks for your feedback!

At this stage, I only tested it by running rc_input start -d /dev/ttyS3 without any error, and confirmed with rc_input status that there were no obvious issues.

I understand this is not a complete validation. I’ll continue to study and explore proper testing methods to ensure everything works correctly.

Thanks again!

Ok, For validation, checking the protocol lock to crsf is necessary.
In my experience, the elrs default baudrate 420000 can not be set by termios, so termios2 should be used(PX4 now use termios), you can refer to my pr.