, you’ve likely hit a wall. Unlike early models, the Raspberry Pi Foundation now only releases . These official diagrams provide just enough detail for hardware designers and hobbyists to build add-ons without exposing proprietary design secrets. What’s Included in the Official Schematics?
The schematic layout separates data traffic to prevent "traffic jams" on the board: Controlled by a VIA Labs VL805 Raspberry Pi 4 Model B Full Schematic