I do have Samsung HD502HJ with BF41-00302A PCB. In the article on your page i can see that in your opinion the BIOS should be in 8819025-tfj2 marvell chip, but on the other screenshots found on internet i can see that it should be in the smaller 8pin chip that is above the marvel.
As my PCB is missing this smaller chip i am wondering if i have any chance to get my data recovered if i resolder the marvell chip to the brand new PCB.
https://www.hddzone.com/blog/fix-samsung-he502hj-pcb-board-bf41-00302a-00/
About BIOS, please refer the attached photo.
You can move the BIOS from your original PCB by using hot-air gun, then soldered it on the replacement board. Please refer: https://www.hddzone.com/hard_drive_pcb_firmware_transfer.html Or you can find an electronics repair shop help you.
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