The processor by Texas Instruments used in the Beaglebone boards had a main CPU plus two small cores inside the die. Unfortunately those two smaller cores didn't get their own compiler until the Beaglebone was many years old and easier to use, more open source products ate TI's lunch in that domain. (Although TI has never been concerned with the hobbyist domain).

But once TI provided that compiler it was easier for people to have the two smaller cores handle peripherals in real time, while the main processor was busy. Those kinds of heterogenous chips are super interesting if you're into bare metal programming.