It's why I'm using Beaglebone Black for a project involving many RGB LEDs that have a timing-sensitive protocol - it has two "programmable realtime units" on-die with the CPU. It's a pair of separate cores (200mhz, IIRC) that can handle in hardware the kind of software bit-banging that needs to be done on RPi, and it shares some memory with the CPU. It's able to process or raise interrupts, too. It can handle ADC, PWM, and probably a few other TLAs that I'm missing.