Gergely

The A5X MAX+ is different from the A5X MAX. This is very similar to the Z28 pro, which also cannot boot from sd card. First I tried your build, but it didn't work with any dtb.

Which image did you try? You can download my build: https://mega.nz/file/mP5Xjaxb#bmtMFajyGCtofYVHcsazahmuPef6da_YR7ML7lG61sQ Flasher script: https://mega.nz/file/LLIXjAJB#Nu5i9R3Vz_5wGs0nYT3O4rXSz8Yi0PCq7U_WC3TxeVU This is outdated, but I use it without a trouble since months. @Reddwarf also tried to install it, but it didn't work for him. I still don't know the reason.

This is the uart connector. All I know about it that it is accessible with unusual speed: 1500000

I remembered one more thing. Maybe you need to erase the emmc. I added the erasing to the script: https://mega.nz/#!LLIXjAJB!Nu5i9R3Vz_5wGs0nYT3O4rXSz8Yi0PCq7U_WC3TxeVU

The error message only shows that the config.ini file is missing. But otherwise based on the output the installation was successful. It should work. Unfortunately, I don't know what the problem is. I uploaded the MiniLoaderAll.bin file that can be found in the android image that you linked. Replace the MiniLoaderAll.bin file in the images folder with it, and try flash again: https://mega.nz/#!PWZ22agZ!egozzjZ6Gi5FnPsNW4RZB_4GdIjGTXN8dVBVvD25zgo I have no other idea yet, sorry.

Exactly which Android image works for you? Maybe we could try the MiniLoader in it.

If your box is still able to enter maskrom-mode, it will continue to work. I uploaded a new version of the script that also flash the gpt partitions. I hope that's what I missed. You can download it from here: https://mega.nz/#!yLAR3AIZ!1RXrDS-1f_y2M50fSokz5PsLcNRXenAzlhPRU_n_C6o Otherwise, what tool did you use to flash the android firmware? (The script can't do it.)

A bad USB cable can cause error like this. Try another. Otherwise, where did you find the stock Android 8.1 image?

What is the output of the script when you flashed an image?

Try my build: https://mega.nz/#F!rWoFkShB!7EYXqve7nVZCySRafN5mVQ

Your device was in maskrom-mode? For maskrom-mode, you need to short these two pins while insert the USB cable (This should work even if your box currently is not boot):

If I have a little time I will write a description and upload the image. You can flash the Balbes image too with the script, maybe it will work. But a few things will certainly not work, eg wifi, led display. I don't know exactly, I didn't tried. My first try was the official rock64 image. Basic functions works with that.

The A5X Max+ is different, it is unable to boot from SD card. You can install armbian to eMMC via usb-cable in maskrom-mode, but it is replace the original Android firmware. I added an initial support for this box to the tvboxes branch (It is not officially supported by the armbian team!): https://github.com/armbian/build/pull/1415 I can upload a flashable image somewhere, if you interested.