alt Hacker NewsDoesn't the lack of a flat memory model make a genral os difficult? The amiga1000 had far less processing power and about the same memory, with no mmu, but that memory model was flat. Did you have to do weird things to work around it?
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What makes general OS difficult on a SoC is usually the lack of hardware virtual<->real RAM address translation accelerator, the MMU.
I guess it's not that important if developers had no raw pointer access so that object can be anywhere dynamically assigned(Java!!! also JavaScript and all interpreted langs). But basically all desktop OS apps are written in C and they always want single consistent virtual addresses to jump around in and none of apps work without the hardware dynamic translation.
Can you expound on this problem a bit? I'm still pretty new to MCUs.
The memory model is flat enough. The problem with the memory is, you only have about 200kB traditional RAM. But then, you have 8MB of PSRAM. But it requires strict 4-byte alignment, and is noticeably slower.
What makes traditional OSs difficult on this platform, is the lack of memory protection. But I am a simple man, I am not writing an OS, all I wanted was a usable shell and an apps installer, so I made that work.