Keyboard EC (KBEC) firmware for the Lenovo IdeaPad 5-15ARE05 on board NM-C811, a 128 KB image packed in a 98.6 KB RAR. NM-xxxx numbers are used by LCFC, Lenovo's own board maker. The embedded controller handles power-on, charging, fans and the keyboard, so a corrupt EC can cause no-power faults. Flash it to the EC or its separate flash chip with a suitable programmer, after confirming NM-C811 on the PCB and saving the original contents.
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 →