We could have pretty decent $8 Linux machines, with USB, screen, touch, audio, MBs or even GBs RAM, if there would be some standard way to sideload fresh GNU/Linux onto billions of retired Android devices.
The $8 Linux Computer
101–110 of 166 posts
Re: The $8 Linux Computer
#102Earlier quoted context omitted.
Ah yes thanks, still pretty good though for on-package for £3-odd (UK price). https://m.aliexpress.com/item/1005004970779483.html
Any experience with this board? Toolchain, etc?
Not yet- I have a maix M1s dock full package on order, so hope to try it shortly. Sipeed supply a connector to be able to flash their board easily, and they seem to have an IDE for various use cases.
I'm hoping the MCU in the chip is the same as the BL602 chip- the 602 has a fully opensource firmware for the radio and cpu, can run zig and lora: https://lupyuen.github.io/
For me, I'm looking forward to using a riscV MCU with a decent amount of ram, as a fixed platform to build an OS on.
Re: The $8 Linux Computer
#103Earlier quoted context omitted.
I think zigbee is more "resilient" because it piggybacks off all the other zigbee devices via mesh instead of each device talking to the central router.
Zigbee is also far lower data rate than even first-gen WiFi, which makes it more resilient. Radio protocols are usually a compromise between 1) range 2) power efficiency 3) throughput 4) robustness. Zigbee prioritizes 2, achieves 1 through meshing, 4 through error correction and other stuff, and mostly writes off 3. Point being it's not just meshing doing the work here, it is overall designed differently from Wifi an…
Note that 802.11 (original) is specified with 50% error correction at MCS 1 aka 1 Mbit/second rate. That is, for 1000 bits transmitted, 500 were data, and 500 were error correction. (Plus all the error detection codes like CRC32 on top of that).
This is a good example of tradeoffs: slower and less throughput, but way more robustness.
Higher MCS levels of 802.11 cut down on error correction to 25% or 10%, achieving more throughput but less robustness.
I dunno how Zigbee does it, but I assume it has more error correction at slower (ie: more reliable) speeds than even WiFi MCS 1.
Re: The $8 Linux Computer
#104Earlier quoted context omitted.
Any experience with this board? Toolchain, etc?
Not yet- I have a maix M1s dock full package on order, so hope to try it shortly. Sipeed supply a connector to be able to flash their board easily, and they seem to have an IDE for various use cases. I'm hoping the MCU in the chip is the same as the BL602 chip- the 602 has a fully opensource firmware for the radio and cpu, can run zig and lora: https://lupyuen.github.io/ For me, I'm looking forward to using a riscV M…
Great, keep me posted on your progress. Just ordered 2. The price point was just too good to pass up for that much horsepower and ram.
Re: The $8 Linux Computer
#105Earlier quoted context omitted.
I would think that Zephyr would be better suited for this. Linux is great for many things, but it can also be overkill.
Generally I would agree with that sentiment, but when we have Linux running on cheap low power MCU grade hardware, why not use it?
I have a pie zero w doing things with its GPIO. It’s super nice to ssh right to the board to update src code without having to go through the flash dance. I know Linux is not “hard real-time” but it’s close enough. All the real-time reqs I have get offloaded to a dedicated pwm breakout and communicated with over i2c anyway.
Re: The $8 Linux Computer
#106Earlier quoted context omitted.
This is a big deal to me. What's stopping normal microcontroller platforms like Zephyr from providing dynamic loading of programs? It'd be great for iteration to have a solid OS that cares about networking and updates and a an application layer you can move fast and break things with without risking soft-bricking your device. I'm currently finding this with interpreted platforms like Espruino and Micropython, but don…
Where would you even load to program to and where from? Typical microcontroller platforms only have a few kB of ROM and RAM, you can't load your application to RAM to run it, it's directly run from Flash. But the internal flash of a MCU can only be erased in pages that can range up to 4k or 8k depending on the platform. So that already limits how many free pages you might have that you could dedicate to an applicatio…
The base PDP-11 had 56KB. Many microcontrollers exceed that.
Re: The $8 Linux Computer
#107Show me one with an integrated serial adapter and I'll buy it. I know how to generally program things via UART, but really would prefer not having to bother with it. It's not a great development experience. Pine64 keep making these silly little mistakes limiting their products' appeal.
The lack of USB serial is just a bug in the first batch
https://gist.github.com/lupyuen/7a0c697b89abccda8e38b33dfe5e...
Re: The $8 Linux Computer
#108Earlier quoted context omitted.
Does it support UEFI with an updateable open source firmware (e.g. u-boot)? With enough kernel mainlining happening this would allow to use any distro image instead of always having to fiddle with custom images.
Yes u-boot. I think Debian, Ubuntu, fedora and OpenSuse are preparing images. FreeBSD possibly too (I think at Tier 2 level/no binary updates). I am hoping it gets first class support from some distro! Definitely don't want to rely on starfive support.
Well, that was the UEFI part of the question: With UEFI you don't need special images built, you can use the generic arm64 image and it will boot as long as things are in the mainline Linux kernel.
Re: The $8 Linux Computer
#109Re: The $8 Linux Computer
#110Earlier quoted context omitted.
Most modern ARM SoCs capable of running Linux have one or more cortex M cores, down from M1s to M4s (I have yet to see M7s). It is precisely for what you describe.
M0. I’ve never seen an SoC with an M1, which is a core specifically designed to be implemented on an FPGA. Cortex-R is also pretty common (R5 on Zynq-7000 and R7 on UltraScale MPSoC, for example)
Indeed, brainfart, thinking too much about the Apple M1. Thanks!