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#1
A20 / Re: My Micro won't boot from M...
Last post by LubOlimex - Today at 09:50:32 AM1. Check if the voltage applied to the power jack is sufficient. The A20-OLinuXino-Micro requires between 6V and 16V DC, maybe test with 12V DC.
2. Test the SD cards. Good software for testing the SD cards is either f3 (fight flash fraud) or H2testW.
3. Try with another software to download the image to the card. I recommend using BalenaEtcher or USBImager software – they are open source source, free, have releases for Windows/macOS/Linux and using them minimizes the chances of a mistake. I've had cases where something odd was written at the start of the SD card that prevented the boot from it.
2. Test the SD cards. Good software for testing the SD cards is either f3 (fight flash fraud) or H2testW.
3. Try with another software to download the image to the card. I recommend using BalenaEtcher or USBImager software – they are open source source, free, have releases for Windows/macOS/Linux and using them minimizes the chances of a mistake. I've had cases where something odd was written at the start of the SD card that prevented the boot from it.
#2
A20 / My Micro won't boot from Micro...
Last post by buntubaby - July 26, 2026, 06:53:12 PMHi everyone,
My A20-OLinuXino-Micro does not boot from MicroSD cards any more.
I've tried 2 different cards (both SanDisk Ultra 16GB) and 2 Olimex images;
* A20-OLinuXino-bookworm-base-20260323-113959.img
* A20-OLinuXino-bullseye-base-20241121-172551.img
The images I wrote to the cards using Ubuntu's Disks app (restore disk image option) and when inserting the cards into my laptop they display the uboot.env file and the other folders as expected.
When powering on the Micro, the red power LED turns on, but no other sign of life.
* No power on USB ports (more precise; my wired mouse's tracking LED will not light up, my wired keyboard's capslock will not turn on; but perhaps there is power to USB),
* no ethernet port LED activity,
* no HDMI signal.
However, when I power the Micro WITHOUT a MicroSD card in it, the ethernet LEDs immediately come to life (both power and activity).
I've disconnected the Olimex SATA connector going to an SSD but that doesnt make a difference.
Any advice or things to try?
My A20-OLinuXino-Micro does not boot from MicroSD cards any more.
I've tried 2 different cards (both SanDisk Ultra 16GB) and 2 Olimex images;
* A20-OLinuXino-bookworm-base-20260323-113959.img
* A20-OLinuXino-bullseye-base-20241121-172551.img
The images I wrote to the cards using Ubuntu's Disks app (restore disk image option) and when inserting the cards into my laptop they display the uboot.env file and the other folders as expected.
When powering on the Micro, the red power LED turns on, but no other sign of life.
* No power on USB ports (more precise; my wired mouse's tracking LED will not light up, my wired keyboard's capslock will not turn on; but perhaps there is power to USB),
* no ethernet port LED activity,
* no HDMI signal.
However, when I power the Micro WITHOUT a MicroSD card in it, the ethernet LEDs immediately come to life (both power and activity).
I've disconnected the Olimex SATA connector going to an SSD but that doesnt make a difference.
Any advice or things to try?
#3
FPGA / Re: Stability Issue with GateM...
Last post by LubOlimex - July 23, 2026, 01:23:37 PMI can confirm that the board hang with your bit. We are now evaluating what can be done, experimenting with different capacitors. The regulators are sufficient from what I see, the consumption for the whole board is less than 2W. I hope fixing this won't break anything else.
#4
iMX233 / Re: State of audio in i.MX233 ...
Last post by xaelsouth - July 18, 2026, 04:12:28 PM #5
iMX233 / Re: is imx233 dead? does anyon...
Last post by xaelsouth - July 18, 2026, 04:09:02 PMSure. Still 'playing' with iMX233. Recently published https://github.com/xaelsouth/random-notes/wiki/On-iMX23. Audio in and out works, but tv-out does not. Not sure about the latter one, but it does not seem too hard to make it work again with recent Linux kernels.
If someone could help to move some of provided patches into U-Boot, Linux or Buildroot - you are very welcome!
If someone could help to move some of provided patches into U-Boot, Linux or Buildroot - you are very welcome!
#6
A20 / Running an Olimex A20 Linux Im...
Last post by mavstuff - July 16, 2026, 05:05:14 PMIf you're looking for a way to run an Olimex A20 Linux image on your local PC for development, here is a simple setup that works on both Windows and Linux hosts.
This setup is useful for:
It provides working screen, keyboard, mouse, and network emulation. With some patching, it it can also show graphics, which I will describe below. As expected, it does not emulate GPIO or other board-specific hardware peripherals. later this image can be used on a real device as this does not touch native boot files.
1. Install QEMU
Tested with QEMU 11.x on Windows 10 x86_64, but should also work well on Linux host
2. Download an Olimex image
For example: A20-OLinuXino-bookworm-base-20260323-113959.img
3. Build QEMU-comaptibe ARMv7 Linux kernel
Notice the kernel must be separately built and applied from QEMU command line and does not interfere with built-in A20 kernel. It does not overwrite the one stored on the SD card image, but remains as a separate file on a host machine. I used Linux 6.12, which at the end boots and works well. The kernels are compatible from the userspace perspective. Also the modules from the SD image are not used and QEMU kernel has to include them in self.
4. Copy the kernel to your Windows machine
Linux Host: linux-6.12/arch/arm/boot/zImage -> Windows Host: linux-6.12-out/zImage
Sorry I used Windows host, but QEMU should also work well on a Linux host
5. Start QEMU
With this basic setup, the serial console and networking are available.
The serial console is accessible via Telnet on:
localhost:4444
You can connect using PuTTY or any Telnet client.
SSH networking also works, allowing you to connect directly to the virtual machine.
Graphical Desktop
Getting the graphical desktop working is a little more involved due to a compatibility issue between the Linux 6.12 kernel and QEMU's VirtIO MMIO implementation. A small kernel patch is required.
This repository includes the required kernel patches, kernel configuration, and build scripts.
Hopefully this saves someone else a few hours of debugging.
This setup is useful for:
- Building and testing executables
- Setting up SSH connections
- Initializing databases
- Performing Linux configuration and package installation
- General application development without powering on the physical board
It provides working screen, keyboard, mouse, and network emulation. With some patching, it it can also show graphics, which I will describe below. As expected, it does not emulate GPIO or other board-specific hardware peripherals. later this image can be used on a real device as this does not touch native boot files.
1. Install QEMU
Tested with QEMU 11.x on Windows 10 x86_64, but should also work well on Linux host
2. Download an Olimex image
For example: A20-OLinuXino-bookworm-base-20260323-113959.img
3. Build QEMU-comaptibe ARMv7 Linux kernel
Notice the kernel must be separately built and applied from QEMU command line and does not interfere with built-in A20 kernel. It does not overwrite the one stored on the SD card image, but remains as a separate file on a host machine. I used Linux 6.12, which at the end boots and works well. The kernels are compatible from the userspace perspective. Also the modules from the SD image are not used and QEMU kernel has to include them in self.
Code Select
git clone --depth 1 --branch linux-6.12.y https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git linux-6.12
cd linux-6.12
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- multi_v7_defconfig
make ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf- -j$(nproc) zImage4. Copy the kernel to your Windows machine
Linux Host: linux-6.12/arch/arm/boot/zImage -> Windows Host: linux-6.12-out/zImage
Sorry I used Windows host, but QEMU should also work well on a Linux host
5. Start QEMU
Code Select
qemu-system-arm -M virt -m 1024 -smp 2 -display sdl -kernel linux-6.12-out/zImage -append "root=/dev/vda1 rw rootwait loglevel=8 console=ttyAMA0 console=tty0" -drive if=none,file=A20-OLinuXino-bookworm-base-20260323-113959.img,format=raw,id=hd -device virtio-blk-device,drive=hd -netdev user,id=net0 -device virtio-net-device,netdev=net0 -device virtio-gpu-device -device virtio-tablet-device -device virtio-keyboard-device -monitor none -serial telnet:127.0.0.1:4444,server,nowaitWith this basic setup, the serial console and networking are available.
The serial console is accessible via Telnet on:
localhost:4444
You can connect using PuTTY or any Telnet client.
SSH networking also works, allowing you to connect directly to the virtual machine.
Graphical Desktop
Getting the graphical desktop working is a little more involved due to a compatibility issue between the Linux 6.12 kernel and QEMU's VirtIO MMIO implementation. A small kernel patch is required.
This repository includes the required kernel patches, kernel configuration, and build scripts.
Hopefully this saves someone else a few hours of debugging.
#7
New Products release / New Industrial Grade Open Sou...
Last post by olimex - July 16, 2026, 01:57:07 PMPICO-EVB enables your Raspberry PI PICO to drive relays and sense High voltage inputs https://olimex.wordpress.com/2026/07/16/new-industrial-grade-open-source-hardware-board-pico-evb-enables-your-raspberry-pi-pico-to-drive-relays-and-sense-high-voltage-inputs/ #raspberrypi #pico #iot #plc #oshw #industial #automation #esphome #homeassistant
#8
New Product Ideas / Re: can a lime 2 or pico 2 xxl...
Last post by oeren - July 15, 2026, 04:24:01 PMQuoteQuoting from ...
all rpi computers are a nuisance in terms of free software. Because no rpi computer will work even partly if you do not give them the non free software they require to run.
Quotepossible for Open Printer to fit it in their design?
Free software people take what they can get. If a free software computer can replace the rpi zero w then it does not matter if the computer has to be put somewhere outside of the printer.
Quotedoes not run GNU/Linux.
I had not put any thoughts into that. I am not a programmer. Therefore my investigations are the investigations of a layperson. And in any case they can be wrong.
I have been told, it is common that printers and 3d printers are run by micro controllers. Suggesting a pico 2 xxl should be able to run an open printer in terms of performance.
On https://www.opentools.studio/ it says open printer will make use of open source print server CUPS. I guess open printer is referring to https://github.com/openprinting/cups
I cannot tell if the cups software can be put on a pico 2 xxl as is. Or should rewriting the cups software be an option for getting the software on a pico 2 xxl, how big a task that would be?
Should a lot of consumers be interested in buying an open printer running entirely on free software the open printer would present a business opportunity for olimex. I think olimex should contact opentools.studio in order to find out if an open printer version running entirely on free software can be made?
#9
New Product Ideas / Re: can a lime 2 or pico 2 xxl...
Last post by oeren - July 15, 2026, 03:50:22 PMQuoteAll three of the boards that you mentioned can run completely open source software.
If you are including the rpi zero w in all 3 of the boards, you are wrong. The rpi zero w requires non free software in order to work.
In fact no rpi computer is able to run entirely on free software. According to a rpi engineer the raspberry pi pico 2 requires no non free software in order to work.
#10
ESP32 / Re: Framebuffer on ESP32-P4-PC
Last post by LubOlimex - July 14, 2026, 11:31:07 AMThere is HDMI demo in the production test:
https://github.com/OLIMEX/ESP32-P4-PC/tree/main/SOFTWARE/ESP-IDF/p4_production_test
https://github.com/OLIMEX/ESP32-P4-PC/tree/main/SOFTWARE/ESP-IDF/p4_production_test