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#1
ESP32 / Re: ESP32-PoE-ISO UART1 issue
Last post by LubOlimex - Today at 08:26:23 AMThe way to test UART of ESP32-PoE-ISO is pretty simple, connect RX and TX (with a jumper wire with female-female connectors) and open terminal and type something and see if there is echo (e.g. what you type gets printed back). If there is echo - the UART is fine and the issue is somewhere else.
I think the issue is just wrongfully using MOD-RS485-ISO, it is not a basic bare convertor. It has a main microcontroller and own firmware, and while it can be used with Modbus or similar, it is meant to be used with own firmware and commands.
I think the issue is just wrongfully using MOD-RS485-ISO, it is not a basic bare convertor. It has a main microcontroller and own firmware, and while it can be used with Modbus or similar, it is meant to be used with own firmware and commands.
#2
A64 / A64-OLinuXino-2Ge16G-IND: U-Bo...
Last post by Brati - May 18, 2026, 04:52:36 PMI am developing a Yocto 5.0 (Scarthgap) Linux image for the A64-OLinuXino-2Ge16G-IND board and have encountered a critical issue with warm reboot that I have been unable to resolve.
Issue:
The board hangs on every reboot (warm reset and cold reset) after the following boot log line:
INFO: BL31: Preparing for EL3 exit to normal world
INFO: Entry point address = 0x4a000000
INFO: SPSR = 0x3c9
[HANG - no U-Boot output]
First cold power-on always works correctly. The hang occurs every time after any reboot command.
Setup:
- Board: A64-OLinuXino-2Ge16G-IND
- U-Boot: 2024.01 (mainline, from Yocto Scarthgap / poky)
- TF-A: 2.10.4 with SUNXI_PSCI_USE_NATIVE=1 SUNXI_PSCI_USE_SCPI=1
- Crust SCP: v0.6.0 (a64-olinuxino_defconfig)
- Kernel: Linux 6.6.85
- Boot device: SD card (mmcblk0)
What I have tried:
- Added Crust SCP firmware (scp.bin embedded in U-Boot SPL)
- Added R_WDOG fix for A64 in reset_cpu() in board.c
- Added PLL6 lock timeout in clock_init_safe() in clock_sun6i.c
- TF-A rebuilt with LOG_LEVEL=40 - confirmed BL31 completes successfully and hands off to U-Boot at 0x4a000000
- U-Boot freezes before printing a single character
The hang is confirmed to be between BL31 exit and U-Boot's first UART output.
Question:
Can anyone please share which U-Boot version and if any specific patches you use in your Olimage builds for the A64-OLinuXino to make reboot work correctly?
Any guidance would be greatly appreciated.
Best regards,
Bratiranjan Acharya
bratiranjan12@gmail.com
Issue:
The board hangs on every reboot (warm reset and cold reset) after the following boot log line:
INFO: BL31: Preparing for EL3 exit to normal world
INFO: Entry point address = 0x4a000000
INFO: SPSR = 0x3c9
[HANG - no U-Boot output]
First cold power-on always works correctly. The hang occurs every time after any reboot command.
Setup:
- Board: A64-OLinuXino-2Ge16G-IND
- U-Boot: 2024.01 (mainline, from Yocto Scarthgap / poky)
- TF-A: 2.10.4 with SUNXI_PSCI_USE_NATIVE=1 SUNXI_PSCI_USE_SCPI=1
- Crust SCP: v0.6.0 (a64-olinuxino_defconfig)
- Kernel: Linux 6.6.85
- Boot device: SD card (mmcblk0)
What I have tried:
- Added Crust SCP firmware (scp.bin embedded in U-Boot SPL)
- Added R_WDOG fix for A64 in reset_cpu() in board.c
- Added PLL6 lock timeout in clock_init_safe() in clock_sun6i.c
- TF-A rebuilt with LOG_LEVEL=40 - confirmed BL31 completes successfully and hands off to U-Boot at 0x4a000000
- U-Boot freezes before printing a single character
The hang is confirmed to be between BL31 exit and U-Boot's first UART output.
Question:
Can anyone please share which U-Boot version and if any specific patches you use in your Olimage builds for the A64-OLinuXino to make reboot work correctly?
Any guidance would be greatly appreciated.
Best regards,
Bratiranjan Acharya
bratiranjan12@gmail.com
#3
New Product Ideas / Re: can a lime 2 or pico 2 xxl...
Last post by LubOlimex - May 18, 2026, 02:50:40 PMAll three of the boards that you mentioned can run completely open source software. Yet there is major difference between the Raspberry Pi product and Olimex products - Raspberry Pi Zero W is not open-hardware, while Olimex provides files used to manufacture their products, when it comes to A20-OLinuXino-LIME2 and PICO2-XXL. These are open-hardware products.
About the software - the official Linux image provided by Olimex for A20-OLinuXino-LIME2 is truly open-source software, and contains no binary blobs. This is mentioned in the Olimage guide here:
https://github.com/OLIMEX/OLINUXINO/blob/master/DOCUMENTS/OLIMAGE/Olimage-guide.pdf
PICO2-XXL doesn't come with own software, the software Olimex provides for PICO2-XXL is based on the RPi SDK, so expect similar software as what Raspberry Pi Zero W uses.
About the software - the official Linux image provided by Olimex for A20-OLinuXino-LIME2 is truly open-source software, and contains no binary blobs. This is mentioned in the Olimage guide here:
https://github.com/OLIMEX/OLINUXINO/blob/master/DOCUMENTS/OLIMAGE/Olimage-guide.pdf
PICO2-XXL doesn't come with own software, the software Olimex provides for PICO2-XXL is based on the RPi SDK, so expect similar software as what Raspberry Pi Zero W uses.
#4
ESP32 / ESP32-PoE-ISO UART1 issue
Last post by bartgrefte - May 17, 2026, 06:54:41 PMMy apologies for the kick.
@ninousf and @_AndreaS_ , did you end up solving it? Running the 16MB build of ESPEasy here, I'm trying to use the MOD-RS485-ISO with HW serial1 on GPIO's 36 (Rx) and 4 (Tx).
So far no luck.
@ninousf and @_AndreaS_ , did you end up solving it? Running the 16MB build of ESPEasy here, I'm trying to use the MOD-RS485-ISO with HW serial1 on GPIO's 36 (Rx) and 4 (Tx).
So far no luck.
#5
New Product Ideas / can a lime 2 or pico 2 xxl run...
Last post by oeren - May 17, 2026, 05:13:02 PMhttps://www.crowdsupply.com/open-tools/open-printer
In the following I am assuming that the software which is running the open printer is free software.
Unfortunately the open printer people decided to go with a rpi zero w. The rpi zero w requires non free software in order to work. In result free software people do not want to use the open printer. On the other hand should it be possible to replace the rpi zero w with a computer able to run entirely on free software the open printer would get relevant for free software people.
Both lime 2 and pico 2 xxl can run entirely on free software correct? If so can I get to know if the lime 2 and pico 2 xxl are candidates for replacing a rpi zero w?
Please do not provide answers if you are not familiar with what free software is in the context of the free software foundation. Thank you.
In the following I am assuming that the software which is running the open printer is free software.
Unfortunately the open printer people decided to go with a rpi zero w. The rpi zero w requires non free software in order to work. In result free software people do not want to use the open printer. On the other hand should it be possible to replace the rpi zero w with a computer able to run entirely on free software the open printer would get relevant for free software people.
Both lime 2 and pico 2 xxl can run entirely on free software correct? If so can I get to know if the lime 2 and pico 2 xxl are candidates for replacing a rpi zero w?
Please do not provide answers if you are not familiar with what free software is in the context of the free software foundation. Thank you.
#6
A64 / Re: Debian GNU/Linux 13 (Trixi...
Last post by mossroy - May 14, 2026, 10:36:02 PMFor information, I've described a different procedure to install Debian 13 on my A64-OLinuXino-2Ge8G-IND boards: https://blog.mossroy.fr/2026/05/14/debian-13-sur-a64-olinuxino-2ge8g-ind/ (it's written in French).
It's far from perfect, but works fine for my use-case
It's far from perfect, but works fine for my use-case
#7
A64 / Re: Bookworm upgrade availabil...
Last post by mossroy - May 14, 2026, 10:30:52 PMIf anyone is interested, I've posted on my blog (in French) my procedure to install Debian 13 on A64-OLinuXino-2Ge8G-IND boards: https://blog.mossroy.fr/2026/05/14/debian-13-sur-a64-olinuxino-2ge8g-ind/
#8
New Products release / Re: Introducing the ESP32-P4-P...
Last post by LubOlimex - May 11, 2026, 10:30:55 AMThis is no the proper place for this reply. Anyway, ESP32-P4-PC has no BAT1 led. Do you mean CHARGE1 LED? Do you have any battery attached to the BAT1 connector?
#9
New Products release / Re: Introducing the ESP32-P4-P...
Last post by bishoff7 - May 11, 2026, 03:04:19 AMHi .why does the BAT1 led costantly have a very dim glow to it constatntly and every second gets slightly brighter then back to very dim again.Regards Chris
#10
A64 / Re: Debian GNU/Linux 13 (Trixi...
Last post by Roman - May 10, 2026, 09:05:36 PMSo, it looks like the u-boot has to be written manually anyway, either with the script from u-boot-sunxi or directly.
The offset is 8 in case of MBR and 128 in case of GPT.
Now it boots as expected untill "Starting kernel ..."
Code Select
# apt install u-boot-sunxi
# dd if=/usr/lib/u-boot/a64-olinuxino-emmc/u-boot-sunxi-with-spl.bin of=/dev/mmcblk0 bs=1k seek=128The offset is 8 in case of MBR and 128 in case of GPT.
Now it boots as expected untill "Starting kernel ..."