[rasz]

Software peripherals were popular in the nineties when using Scenix 50MHz PIC clones https://hackaday.com/2022/08/17/chips-remembered-the-scenix-...

In 2006 we got 8 core risc chips running at 80MHz. 0.25 IPC = 160MIPS https://en.wikipedia.org/wiki/Parallax_Propeller

in 2008 XMOS xCORE came out, instead of 8 cores in parallel you get 1-2 CPU tiles running at 400-500MHz partitioned into 4-16 virtual cores. 1 IPC = 1000MIPS. 1 cycle IO. Super popular in audio devices where it bitbangs all sort of serial audio interfaces while performing DSP. Newer models have DSP instructions, and the newest ones might even have something for NNs.

"Each tile has 8 active logical cores, which issue instructions down a shared four stage pipeline. Instructions from the active cores are issued round-robin. If up to four logical cores are active, each core is allocated a quarter of the processing cycles."

https://www.xmos.ai/download/XS1-L16A-128-QF124-Datasheet(1....

2012 TI sitara AM335x (beaglebone black) has dedicated IO cores.

[synergy20]

First time heard about Scenix/Prallax_Propeller. Maybe it's more complex for DIYers or not as well-known as Raspberry Pi?

AM335X has PRUs yes, but it's not MCU anymore.