Unofficial CyanogenMod 13.0 build dated 2022-05-27 for the j3xlte device codename, packed as a 375 MB ZIP. It is a custom Android ROM, not a laptop BIOS, and is normally installed through a custom recovery such as TWRP rather than with an SPI programmer. Make sure the codename matches your exact phone variant before flashing, because a build for the wrong model can fail or soft-brick the device. Back up the existing system, data and EFS partitions first so the original state can be restored.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @esquemaseletricos. Enginerys does not host this file.
How to open a .zip file
Compressed archive that every operating system opens without extra software.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →