USB3 Gen T: An accelerated USB3 for USB4 domain

The USB4v2 Specification introduces USB3 Gen T, an accelerated USB3 tunneling protocol designed for the USB4 ecosystem. This innovation addresses real-world needs like rapid data exchange and expanded device connectivity by efficiently utilizing USB3 bandwidth within USB4.

USB3 Gen T becomes a new "USB3 GenT Adapter" within the USB4 Device Router. Its acceleration stems from significant modifications at both the Link and Protocol layers, even though the core USB3 protocol stack remains unchanged. Link layer enhancements include deprecated framing symbols, updated link command formats, simplified control words, increased credits and buffer sizes with command aggregation, and an optimized Link Training and Status State Machine (LTSSM) for faster reactions. At the Protocol layer, updates accommodate increased bandwidth by expanding the size of SeqNum and NumP fields in USB3 packets.

Furthermore, Gen T's "pass-through" tunneling updates the USB4 Hub, allowing direct USB3 traffic exchange between upstream and downstream ports without intermediate USB3 modules. Siemens EDA offers a comprehensive, emulation-ready USB4v2 Peripheral solution with USB3 Gen T support, aiding in early verification of USB4 IP, SoC, and system-level designs. This solution supports various protocols and platforms, ensuring robust testing and debug capabilities for the new USB4v2 standard.