SMSC KBC1126NU is an 8051-based Keyboard Controller (KBC) and Embedded Controller (EC) widely used in laptops, most notably in HP EliteBook series (e.g., HP EliteBook 8470p). Google Open Source

I should mention why patching is important—like corrections for design issues, errata in specs, or updated timing parameters. Maybe the patched version addresses a problem in the original, such as a voltage tolerance mistake or a timing issue that affects performance.

Lab and reverse-engineering efforts have revealed multiple errors in the leaked kbc1126nu_datasheet_v0.9.pdf :

2.2 Common Errors in the Leaked Datasheet

  • Datasheet Status: You will likely not find a full public datasheet. However, pinouts can often be derived from schematics of laptops that use this chip (e.g., Dell LA-C291P, various Lenovo sockets).