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USB Enumeration Dance

Walk the sequence from mechanical connect through Set Configuration to a mounted filesystem. Every step is mandatory, every step is fast.

Host (xHCI)USB Devicemechanical connect1. Plug inUSB PD / orientation2. CC negotiationSE0 for 10ms3. Bus resetSETUP 80 06 00 014. Get Device DescriptorSETUP 00 05 XX 005. Set AddressSETUP 80 06 00 026. Get ConfigurationSETUP 00 09 01 007. Set Configurationusb-storage / hid / cdc8. Class driver loadsbulk / interrupt / isoc9. Normal I/O begins
Step 1 / 9Plug in

The connector mates and power arrives first. Once the CC pin on USB-C sees the device resistor, the host knows something has been attached and can start discovery.

Arrow keys to walk the handshake · R to reset

Tap dots to jump to any step

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