Potential All-in-One Single Board Computers

ODROID-N2+ with 4GByte RAM - $83.00 in stock Feb '23
www.hardkernel.com/shop/odroid-n2-with-4gbyte-ram-2/

S922X CPU - Amlogic
androidpctv.com/comparative-amlogic-s922x/

Datasheet:
dn.odroid.com/S922X/ODROID-N2/Datasheet/...c_Datasheet_V0.2.pdf

Bari wrote:

ODROID-N2+ with 4GByte RAM - $83.00 in stock Feb '23
www.hardkernel.com/shop/odroid-n2-with-4gbyte-ram-2/
 

I'm playing with an N2+. One of the Armbian Real time experts is guiding me. I built and installed the PREEMPT_RT 6.2 rc3 kernel yesterday and it worked. I have not been able to measure latency yet. Linuxcnc from the Bookworm repos failed so next step is to build  Linuxcnc.  Hes keen to get me onto Xenomai 4 which will be interesting... If I can convince Linuxcnc to recognise it. I also played around with ChatGPT who wrote out some quite plasusible timer interrupt code for hardware stepping. Some help might be needed when I get to that!

 

I would call it some deceptively convincing timer interrupt code, If you want real code I think you need codex access, to get real code and not scrapped platform.openai.com/docs/models/codex

I'd look into Arch or Gentoo for anything ARM+Linux if you want it to work. The OrangeCNC dev (LinuxCNC on Allwinner) gave up the whole project after getting it working since Armbian kept breaking the device tree overlays.

allwincnc.github.io/index.html

Do you have a link to a working Armbian image for the ODROID-N2+? Armbian posted lots of images for the Allwinners/OrangePi's that were broken and many of us just gave up trying to find one that worked. They seem to post broken with working and no warnings are given.

I see that there is already a thread started on this:  forum.linuxcnc.org/18-computer/48113-odr...raspberry-pi?start=0

 I'm playing with an N2+. One of the Armbian Real time experts is guiding me. I built and installed the PREEMPT_RT 6.2 rc3 kernel yesterday and it worked. I have not been able to measure latency yet. Linuxcnc from the Bookworm repos failed so next step is to build  Linuxcnc.  Hes keen to get me onto Xenomai 4 which will be interesting... If I can convince Linuxcnc to recognise it. I also played around with ChatGPT who wrote out some quite plasusible timer interrupt code for hardware stepping. Some help might be needed when I get to that!

Just so the community is aware, adding Xenomai 4/EVL/dovetail support in LinuxCNC would be a pretty big project. Currently, LinuxCNC supports RTAI, PREEMPT_RT and maybe Xenomai 3 still. RTAI and Xenomai 3 uses IPIPE, EVL is the replacement for IPIPE but still retains the co-kernel approach.

evlproject.org/dovetail/

evlproject.org/core/user-api/

source.denx.de/Xenomai/xenomai/-/wikis/Dovetail

cakeslob wrote:

I would call it some deceptively convincing timer interrupt code, If you want real code I think you need codex access, to get real code and not scrapped platform.openai.com/docs/models/codex

Why I said Plausible.

Bari wrote:

Do you have a link to a working Armbian image for the ODROID-N2+? 

Bari yes, I've done it a couple of ways but have not got it nailed for preempt-rt yet.
Using their build environment, I have built working images for their current (6.1) and edge (6.2) kernels with Bookworm and xfce. Linuxcnc installs from the repos.

Building Preempt_rt has eluded me so far. uname -v shows as preempt_rt  but internally, its broken as none of the linuxcnc thread related stuff works.
Also their standard download for Bullseye minimal CLI works fine. See: www.armbian.com/odroid-n2/
You can install a graphic environment with:
I tried Tasksel this morning on a minimal cli and it worked. It was just a bit of a shock to see a Debian logon screen just as I was getting used to Armbian's logon screen

There are some issues with Odroids pettitboot mess which is proprietray code on flash ram. eMMC  images needed to be first booted through petitboot. current Bookworm then booted without petitboot.  edge Bookworm failed to boot. ( I guess thats why they call it edge!)

We are building preempt_rt to a .deb file which can be installed with dpkg -i. Once we get it working, we should be able to build a RT image and optionally install or build linuxcnc inside their build environment so  its all in the image.

The sunexi based systems should have good RTsupport as my helper works on that platform and all things RT....

Bari wrote:

Do you have a link to a working Armbian image for the ODROID-N2+? Armbian posted lots of images for the Allwinners/OrangePi's that were broken and many of us just gave up trying to find one that worked. They seem to post broken with working and no warnings are given.

I see that there is already a thread started on this:  forum.linuxcnc.org/18-computer/48113-odr...raspberry-pi?start=0

Bari, details on how to install Armbian and the PREEMPT_RT kernel are now on the other thread you linked.

This looks great for a Remora port, Rpi2040 + Ethernet for ~$18: docs.wiznet.io/Product/iEthernet/W6100/w6100-evb-pico

linuxgizmos.com/wiznet-board-features-ra...net-controller-chip/

W6100-EVB-PICO is sold for $17.58 on Mouser.com

those wiz dev boards are slick and cheap. I think mbed6 supports rpi2040, but I dont know how to do the hard parts.


I did get the stm mcu side of this all in one unit. Next is to do is the hard part, linux part for rockchip 3328, and then probably the hardest part will be porting remora.c comp to rockchip

www.aliexpress.com/item/1005004509354702...00029429564667%21rec

I have the stm mcu almost working on this unit, but the DMA is hard. I also dont know if people can get CM4 units yet either, so it may be moot. otherwise it would need some allwinner remora.c port

www.aliexpress.com/item/1005004478452192...ider_2004642790052.1


starting from the mcu and working backwards is a huge pain in the ass though.