Tiny Linux Boards for special projects

Hardware
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I have a small depth camera I plan to use for a palm gesture interface sort of theremin like with hopefully more nuance, I might end up using an ESP32-S3 to do a simple blob geometry scan.

Depth Cam
Depth Cam800×529 99.9 KB

There are some interesting new tiny Chinese Linus boards with Ghz clock speeds that might serve me better, (they might make a good synth engine to upgrade an old keyboard’s sounds.)

I’m mentioning it now after a survey of what’s available during the 11/11 - 11/17 Aliexpress sale, saving some 20% on a purchase. (I mention some prices that include the shipping charge, items marked with " $4 off every $20" qualify for the extra discount)

Looking at some new Chinese made tiny Linux boards geared for embedded video AI, that might suit my odd idea…

Luckfox-Pico Based on one 1.2 Ghz Rockchip RV1103/06 using an ARM Cortex-A7 + RiscV
Luckfox PickBoars

www.aliexpress.us/item/3256805897424636.html

Decent Guide

Offers 6 variations from $9 to $15 with 64Mb or 128Mb ram, 1Gb Flash

Milk-V Duo Milk-V Duo | Extremely Cost-Effective Ultra-Compact Embedded Linux Development Platforms

RISC-V Milk-V Duo with RJ45 option
RISC-V Milk-V Duo with RJ45 option880×260 286 KB

Dual Core 1Ghz CV1800B RISC-V, 64 Mb, 16 bit audio can be found for $8.20

$15.26 with optional Eithernet connector
www.aliexpress.us/item/3256805977614076.html

There’s an expansion board that doesn coast much more than the lone Eithernet connector option.
Milk-V IO Expansion Board

These boards have more horsepower than some of older Allwinner boards I have seen before.
The Luckfox-Pico documentation looks good, although the pages of Linux configuration steps are beyond me (I need to burn an image and plug it in like a Raspberry Pi)

Looking for something with stronger support and community, I ended up considering the:
Orange Pi Zero 2W

Orange Pi Zero 2 W
Orange Pi Zero 2 W1167×616 306 KB

http://www.orangepi.org/html/hardWare/computerAndMicrocontrollers/details/Orange-Pi-Zero-2W.html
Based on the RaspberryPi version it offers 1, 1.5, 3 & 4 Gig Ram options and has a 24 pin expansion connector that might be suitable for project specific circuit PCB connections.

Orange Pi Zero 2W with expansion board
Orange Pi Zero 2W with expansion board800×569 263 KB

They offer multiple systems (not as fresh as RaspberryPi’s),
Android 12 TV, Debian11, Debian12, Ubuntu22.04, Ubuntu20.04 ，Orange Pi OS（Arch）, it might work with OpenWrt (There are some 9 earlier ORange Pi models listed) which I believe is the mini Linux used in WiFi Routers, one might be able to piece together a minimal system that runs well from flash (that seems ideal for the tiny boards).

After considerable research I found one can get a 1 GB for $14 total cost, for development a 2 Gig with Expansion board can be had for $28.83 (with the $4 discount until 11/17)
www.aliexpress.us/item/3256805947124210.html
The factory ‘store’ is just a couple dollars more with out the 11/11 special.
Any comment on the Orange Pi wound be appreciated…

3 Likes
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If you search the forums you’ll find people have got Zynthian working on the Orange Pi in some form. But they’ve not left much to go on so if you’re not confident in building and maintaing a linux distro it might not be the cash saving that it initially looks like.

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Yep! As @Baggypants says, there are hundreds of SBCs that come and go. Few (if any) actually surpass the bang-for-buck you get from the Raspberry Pi and very few survive (with support) for any significant period of time. The Raspberry Pi is extremely good value in that it is not only (mostly) affordable to purchase but also provides very long support for all incarnations. We are lucky that it exists. That is not to say that other boards are not worthy of a play - indeed my draw is full of such bits and pieces which occasionally prove to be handy for a project but I wouldn’t want to create a project or product that I need to support based on these things. It is bad enough when the members of the family complain about the kitchen lighting controller not working without the rest of the world joining in!!!

Thanks for the pointer to the Aliexpress sale. I may be tempted to part with money I don’t have for something I didn’t know I wanted and certainly don’t need…

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At least it’s good to know I can take a 10 mile drive to pick up a Raspberry Pi 5, it’s just a little too expensive for me, when such things can be done on my desktop.

I would like to make the sensor interface I am tinkering with to be as compact as possible…

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LOTS of this sort of stuff goes on around here…

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For a sensor interface I would recommend using a microcontroller rather than a SBC. Arduino made these popular and accessible but there are many options. They usually don’t have the power of a computer like the Pi but are small, low powered and instant-on (no OS). I like the STM32 range of microcontrollers but have also used Espressif and Microchip based boards. The Raspberry RP2040 is a nice new chip. Development boards cost just a few pounds / euros / dollars. I tend to use PlatformIO within VScode to develop firmware for microcontrollers. You can use the Arduino or alternative framework, depending on which chip / board you are using. I often is the Arduino framework to develop something rapidly and what a wider community (maybe with less technical experience) are involved but will often use a lower level framework for production devices.

1 Like
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There’s a chance I may need to use OpenCV or TinyMV for some crude image analysis, which tend to require lots of horsepower.
Looking at a pretrained hand pose tensorflow library’s benchmarks:

MediaPipe Handpose consists of ~12MB of weights, and is well-suited for real time inference across a variety of devices (40 FPS on a 2018 MacBook Pro, 35 FPS on an iPhone11, 6 FPS on a Pixel3).
Too slow for embedable processors, my approach, treating the palm as a simpler ‘blob’ with fewer sample points should help.

(My biggest problem with embedded Raspberry Pis is the start up time (the zero is soo sad), and clean shut down complications, TinyLinux-Picore with a min size of about 40Mb (zipped release is 27Mb) looks good for simple enbeded applications. There’s a Tiny Core Linux book.

The ESP32-S3 is their AI oriented microprocessor with vector registers , there are imaging benchmarks 50 times faster ( for audio projects, FFTs 16 bit Fixed Point is about 10X faster than original ESP32 )
https://espressif-docs.readthedocs-hosted.com/projects/esp-dsp/en/latest/esp-dsp-benchmarks.html

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I’ve received an OrangePi zero 2W last week.

I will burn armbian minimal image and run setup_system_raspioslite_64bit_bullseye.sh

ASAP

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Is possible install Zynthian in RPI with raspbian previously installed?

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Yes, but it will ruin everything, take ages and there are no instructions. Get a 2nd memory card and save yourself the heartache.