There are usually two ways of looking at this question before answering:

• The first is: which architecture do you think will probably still be around many years into the future.
• The second is: what chips being sold today that will still be sold many years from today so that a manufacturer can count on a continuous supply line over the life of their product (years and years to come).

Regarding the first point, I would say that the 32-bit ARM-based microcontrollers Cortex-M are a very safe bet for many years to come.

However, they have one problem, they are not produced by same company, they are available from many different vendors, and each vendor has its own spin because ARM licenses the CPU, but individual chip makers add on their own peripherals and design it according to their vision.

So this leads to the second point. Microchip, which sells many ARM Cortex-M parts in addition to selling its very own famous 32-bit PIC32 (based on MIPS) and 8-bit and 16-bit PIC microcontrollers, it has a very good reputation, compared to many of its competitors, for not discontinuing parts ( which usually known as EOL, or end-of-life for a certain product).

As an example, Microchip still sells the same 8-bit PIC 16F84A microcontroller that it introduced over 20 years ago (1998). So you don’t have to rewrite your software, or even rebuild the layout of your board again.

So whether it is 8-bit, 16-bit, or 32-bit, I always suggest Microchip as it’s your best bet for future-proofing.

You have to keep in mind Future-proofing is about not having to rewrite all your software.

Therefore, the most future-proof is “any microcontroller that has a C compiler”.

Which means all your software will be written in C.

And – here’s the future-proofing – any new microcontroller will have a C compiler on launch day – because the manufacturer knows that their fancy new toy is doomed without it, Microship Microcontrollers also fits in this category