BIOS firmware archive for a Positivo laptop on the NH4CU6 board, with NH4CUXX 6L also given in the name. That is probably a multi-layer board variant marker, but the exact meaning is not certain. Positivo is a Brazilian brand that sources boards from outside manufacturers. The dump can be written to the SPI flash with a programmer when the machine does not boot. Check the board code on the PCB, save the original chip contents, and make sure the image size equals the chip capacity.
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 @biosarchive. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →