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Comment by tyingq | Hacker News Reader

I think "esp32 like thing" is probably a closer comparison.

That thing clocks a 400MHz out of the box and has coprocessors .. I'd also guess that risc-v isa is more performant than esp32's one (super wild guess). Let's say it sits in the middle :)

The distinction to me is software; if it runs Linux or such, it's a computer. If I have to provide "firmware" then it is a microcontroller.

That distinction is getting blurrier and blurrier every day with the ability to flash firmware to some MCUs such that they run Linux. :)

In my opinion the line to draw is support for a privileged mode/protection rings/memory protection. Anything without that can run μClinux at best, which isn't much better than an RTOS. Without process isolation an operating system isn't very "general purpose."

There are Fedora and FreeBSD builds for RISC-V. This particular item seems to have only 8MB though, so not really in (most people's) "computer" realm. ;)

Oh man I was so happy when I migrated from a PC 386SX with 2MB to a Pentium 75 with 8MB!

I went similarly from a 286 with 1MB to a Pentium 166 with 16MB.

A joke about a memory-hungry program use to be that EMACS stands for Eight Megabytes And Constantly Swapping.

ELeven Exabytes and Constant TRashing Of Nodes

RISC-V has a base ISA and many extensions, several of which are virtually required to run a "real" OS with features such as virtual memory. Every build of Linux I've seen for RISC-V is for an RVGC processor with an additional privileged mode.

Theoretically it should be possible to run "Linux" on a glorified microcontroller like the OP with μClinux, but I haven't seen that used for "real" work. It certainly couldn't be used as a general purpose OS.

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