I strongly suspect it is the 8051 core. It has good maturity and is produced by many many companies.
Yet the 6502 onwards were more popular before the 8051 was (am I right?). What about the 68H11? is it popular at all? Ive seen many references to powerpc-based MCUs but never bothered to dive in. Are they used around much?
I was opening an MP3 player at home and gave myself an exercise to list probabilities of various chips I might run into. ARM7 was on top of my list (I think I'd use it in an MP3 player), but found a 16bit ST chip and an ST MP3 decoder.
And then I see names like the dragonball, rabbit, and other stuff I feel I really should know about and dont. Has civilization been built on the bones of the 8051 or am I self-centric?
As a side question shamelessly shoved in, do people really use the PIC, or does Microchip make its money from students?