USB 4 is supposed to fix this by basically removing all the optionality.
Of course I don’t know how you tell if a device/cable is reliably USB 4 or not.
Of course I don’t know how you tell if a device/cable is reliably USB 4 or not.
You mean, it's going to make it even more confusing by leaving in most the optionality. Intel's "Thunderbolt 4" certification removes (some of the) optionality. Detailed explanation here: https://old.reddit.com/r/UsbCHardware/comments/mjz2pu/usb4_a... and here: https://old.reddit.com/r/UsbCHardware/comments/mjz2pu/usb4_a...
Relevant quote:
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Thunderbolt 4 is Intel's specific branding and certification program for its USB4 implementation. Thunderbolt 4 takes USB4, and turns on a bunch of the optional features and makes them mandatory (TBT4) requirements.
Among those optional features are:
- 40Gbps required (base USB4 spec allows 20Gbps-only hosts)
- Thunderbolt 3 backward compatibility (base USB4 allows host to skip TBT3)
- PCIe tunneling support required (base USB4 allows host to not support PCIe)
--- end quote ---
USB is a textbook study in how to design by committee and create easily avoidable problems out of thin air
Actually let’s go back to DB-25. Each pin can be one “feature” so you can identify which features a device/cable support by looking for which pin(s) are missing.