[RetroTechie]

8051 was once big in industrial applications like PLCs.

Somehow I doubt much has changed. In such applications, reliability + maturity of hw/sw ecosystem is much more important than raw speed or design innovations a competing architecture might bring to the table.

So 8051 based parts may see the occasional process shrink, addition of new peripherals, or new IC packages, I/O pin counts, operating voltage etc.

But I'd doubt any designer worth their salt would dare touch that core architecture unless their life depended on doing so. :-)

[duskwuff]

8051 is quite popular in new designs as a low-cost embedded controller. You don't see it as often as a discrete component [1]; it's more frequently embedded in more complex devices, like as controllers for USB peripherals or even for startup sequencing in larger parts.

[1]: Although that is a thing too; there's a number of manufacturers like Silicon Labs with extensive lines of modern 8051-based mcirocontrollers.