Добрый день.

I need a full flash content of the DGS-1510-20 HW:A1. Has anybody a dump of the flash chip?

Thank you in advance.

It is suitable?
https://ftp.dlink.ru/pub/Switch/DGS-1510-20/

It is hard to say. The whole dump should have 32MB. It includes some kind of bootloader, operating system but this file looks as an update only. I need binary dump of the chip.
I unsoldered the chip and put it into programmer. I have found a lot of garbage inside like after unsuccessful flashing. I can reprogram the chip in the programmer and solder it back to board.

Pandemonium6
You can download this from the official D-Link website:
https://dlink.ru/ru/products/1/1910.html
There are also special forums on network equipment:
https://forum.openwrt.org/
https://4pda.to/forum/index.php?showforum=617
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What you were given a link to can be sewn with a programmer.

Thank you for your involvement :) Unfortunately I can't find bios for programmer. It should be 32MB as uncompressed.