Hesoolver 2-6-4 Page

The two primary nodes operate in a master-observer configuration:

They communicate via a high-bandwidth, low-latency interlink dubbed the Hesoolver Crossbar. If Node A fails, Node B can assume full control within 15 ms. Hesoolver 2-6-4

The Heise Method is famous for being a "pure" method. Unlike the CFOP method (used by most speedcubers) which relies on memorizing dozens of algorithms, Heise relies on intuition and block building. It is often considered the most elegant way to solve a Rubik's Cube. The two primary nodes operate in a master-observer

The method is generally broken down into 4 main steps (which may be what your "2-6-4" reference was hinting at). Each state variable updates at 1 kHz, with

These represent the engine’s internal model of the problem space:

Each state variable updates at 1 kHz, with cross-coupling terms defined by a 6×6 Jacobian matrix recalibrated every 100 cycles.

This is the most difficult part of the Heise method and where the "4" in your search might apply (solving the remaining pieces).