Hacker News

Sylphide OS: a general-purpose OS for microcontroller-based computers(projects.freehackers.org)

46 points by iamnothere 6 hours ago | 13 comments

> On top of that, Sylphide OS adds:

> drivers for mouse, keyboard, display, storage and network

and couple lines later

> What you don't have yet, but definitely planned:

> storage (microsd, usb) > network (ethernet, wifi)

I'm not gonna be angry at false advertising, but OS attempts only become appropriate to discuss once you made drivers and actually ran stuff on physical hardware

Before that point it's just one of the many dozens and dozens other half-efforted attempts at OS that have been done over and over to death by now

[–] iamnothere 3 hours ago

Well, given that it’s built on FreeRTOS, this stuff should be fairly cheap to implement. I think you’re being a little overly critical for an early stage project that fills an interesting niche (GUI OS for MCUs).

[–] Rochus 3 hours ago

> Olimex esp32-p4-pc, the flagship product: new, powerful

That's a very cool board, but pretty tricky. Great idea to run an old Mac OS on it. I try on and off to port the Oberon System 3 to this board since I received it in February. The display already works pretty good, but still a lot of road blocks.

[–] iamnothere 3 hours ago

Oberon would be a great fit for this board, your efforts are appreciated.

It’s amazing how these inexpensive “MCUs” (not even sure you can call them that) are overtaking old PCs now.

[–] Rochus 3 hours ago

Thanks, I hope I'll be able to get it done in a timely manner. Currently I have to decompose the statically linked inner core because it doesn't fit into the dedicated memory slot anymore. Did you also have issues with the ttyACM0 connection which starts to drop regularly under certain conditions?

It's indeed amazing that these MCUs essentially correspond to or even exceed the performance of the original Ceres systems in the nineties. The Oberon System and also the later AOS/Bluebottle multi core system are particularly suited for today's MCUs because they don't assume an MMU.

[–] iamnothere 3 hours ago

Oh, I’m not the developer of this, I just follow these sorts of projects because I’m interested in alternative OSes and particularly OSes that run under constrained environments. I haven’t personally tested it. There’s several of these under development now, as well as many emulators; the ESP CYD (and clones) seems to be a favored target.

[–] karlkloss 1 hour ago

On one hand: Cool!

On the other hand: I have a lot of old hardware in my 'too good to go' garbage bin that can run a full fledged Linux, so what.

[–] irdc 5 hours ago

If it's running on MMU-less systems, I'd be interested in how it loads multiple programs into memory: does it need to relocate each program binary? If so, doesn't that preclude using execute-in-place (XIP)?

[–] Arelius 5 hours ago

Generally, running in a MMU without static task config would require relocatable binaries. I'm not sure why it'd preclude execute-in-place. As a relocatable binary should be executable from generally any address space. However I suspect that hardware without an MMU is not super likely to be able to support XIP.

It is based on FreeRTOS, so it should be fairly well documented.

[–] dvdkon 4 hours ago

> I suspect that hardware without an MMU is not super likely to be able to support XIP.

This seems strange to me. Don't most microcontrollers support executing directly from flash? Some even can't execute from RAM.

Though I agree with the main point, you can compile code as "PIC" - position independent code, and not bother with (ELF) relocations except for linking.

[–] ranger_danger 2 hours ago

> Don't most microcontrollers support executing directly from flash?

Yes... I presume they meant XIP for multiple programs at once, since you'd need an MMU for that.

[–] actionfromafar 2 hours ago

Or the program use relative addressing.

[–] topspin 1 hour ago

"COM" programs as seen in MS DOS and earlier CP/M systems contain only relative addresses, and can run from any "segment" of RAM, as the addresses are relative to the value of a segment register. This was used to load "background" services, typically servicing hardware devices.

MCUs with MMUs are starting to appear, such as the ESP32-S31.