[cpgxiii]

You probably aren't using some weird SOM, though. There is a bit of an unstated exception of "unless said SBC/SOM has specific hardware that is necessary/particularly valuable for your product/project". For example, if you need GMSL you are probably not going to be picking Intel, even though ADL-N and the bigger processors support MIPI, simply because no one else does and the documentation/support for it is basically nonexistent. Designs with closely-coupled A/M/R cores, or CPU/MCU/FPGA hybrids like Zynq would be others.

But generally projects which are choosing some random SBC aren't using any of these features, and are just suffering the pain/imposing it on their users for no good reason.

[schaefer]

again, just an oppinion, but it feels really weird to hear you find "exception after exception", when the net result that you've ruled out more real world robotics projects on ARM than likely exist on x86 that you're suggesting should be the "norm".

you've ruled out the entire NXP ecosystem, the entire Nvidia Jetson ecosystem, the entire AMD/FPGA/Zynq ecosystem, even perfectly good options like beagle-board .... who else?

incidentally, you've also ruled out this project - as they are using an M7 microcontroller to meet their hard-real-time timing constraints...

[adrian_b]

The other poster had said nothing about microcontrollers, e.g. about the various MCU models based on Cortex-M cores.

Some things are best done with a microcontroller, and those are not suitable for being done with a general-purpose CPU either based on Intel/AMD or on Cortex-A cores. Actually there are many projects that mistakenly use something like a Raspberry Pi instead of a better and cheaper implementation with a microcontroller, e.g. one based on Cortex-M7 or its successor, Cortex-M85.

The other poster said that where you do not want a microcontroller, but you want to run a standard operating system, e.g. Linux, then the best choice is much more frequently a SBC with an Intel Alder Lake N or Twin Lake CPU, as these not only have a better performance per dollar than the ARM-based SBCs, but they also avoid any software problems and future maintainability problems.

Unfortunately, during the last few months the price of Intel-based SBCs has been affected by the fact that most of them do not have soldered memory but they use one SODIMM memory module. While you can buy an Intel Alder Lake N based SBC for $100, buying today a SODIMM for it may cost as much or more, depending on the amount of memory with which you are content.

The ARM SBCs that come with soldered LPDDR memory have initially been less affected by the price hikes, though now even for them the prices are rising.

[cpgxiii]

I think you're missing my point entirely. If your project needs specific hardware, you have to use that specific hardware (the obvious examples of which would be Jetsons or Zynq/Zynq-like or something ASIL-D or something that tightly couples "A"/M/R cores together, or you are stuck using a SoC from Qualcomm for cell connectivity). There are a lot of projects that do fall into that category.

There are also a (much smaller) number of projects that will legitimately see the kind of scale of production that justifies aggressive cost optimization for the compute platform, either in terms of designing their own around a SoC or picking some SBC/SoM that they can get a good deal on, where the significant additional up-front engineering cost is outweighed by the production savings (and where the desire/need to keep a fixed platform means the often limited platform support from the vendor is less restrictive).

But a large number of robotics projects (basically everything in the research sphere) - this one very much included - just need "some computer" for general-purpose use. They are already separating realtime control onto a separate microcontroller board. For these projects, it is almost always committing a "premature pessimization" of picking some weird SBC. You are signing up for worse CPU and GPU performance, stability, and development future for very little reward.