86 lines
1.6 KiB
Markdown
86 lines
1.6 KiB
Markdown
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# Notes for the talk's outline
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## About Me
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* Based in Singapore
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* Hardware and software
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## Outline
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1. Project History
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2. Why a new OS?
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3. What can it do?
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## Project History
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### Novena: A really open laptop
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We always wanted to make a laptop. Decided to give it a shot to see what happened.
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The processor in this was "relatively large" -- ARM Cortex A9
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Ran Linux
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### Chibitronics: Programming for 8-year-olds
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This had a "relatively small" processor -- ARM Cortex M0 with 4 kB RAM and 32 kB flash
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We got to know this chip really well
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* Bit-banged USB
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* AFSK demodulation
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* https://ltc.chibitronics.com/
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Ran ChibiOS and a very custom program
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### Precursor: Secure communications device
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* FPGA-based (any processor you want!)
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* 16 MB RAM
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* 128 MB storage
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## Why a new OS?
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Two major markets:
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* MCU
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* No MMU, maybe an MPU
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* <= 1 MB RAM
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* <= 4 MB storage
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* CPU
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* MMU designed for multiple processes
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* >= 64 MB RAM
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* >= 256 MB storage (external)
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## What can it do?
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* Kernel is 17 ksloc
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* 6k of that is a RISC-V disassembler for optional GDB support
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* Threads
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* Processes
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* Tier 2 Rust support
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* libstd
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* Entire project built on *stable* Rust
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## Other features
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* Fully Rust
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* Microkernel
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* Stable channel
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* Requires an MMU
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* Interrupts in userspace
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* Each page of memory is mapped once
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## Xous Organization
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* Kernel is single-threaded
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* Services use well-defined API calls
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* All drivers provided in user space
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* Each page of memory can only be lent once
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## How can I use it?
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* Talk to system vendors -- get them to include MMUs!
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* Emulation is easiest -- Renode support
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