Lenovo NM-C421 firmware for the Realtek RTS5455 Type-C controller, sized for a 128 KB flash chip, with CRC32 0xF2E7DC40. NM-xxxx board numbers follow the LCFC scheme, Lenovo's in-house ODM. Write the image with a hardware programmer when USB-C charging or alt-mode output is lost due to corrupted controller firmware. Confirm the chip on the board is 128 KB and the board number matches, back up the original, and check the checksum after extraction.
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 @biosdumpcomputer. 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 →