Specifications

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USB—Device States (2 of 3)
 Resume
 Any bus activity brings device out of suspend
 Host places bus in Data K state for 20 mS then low speed EOP
 Remote wake-up device drives the Data K state for 1 mS to 15 mS and then places
drivers in High-Z state
 Powered
 Device has been attached to the USB port and draws power from VBUS
 It has not been reset
 Default
 Device has been reset from a powered state and has not been assigned an address
 It responds only to endpoint0
 Addressed
 Device has been assigned its unique address from the host
 Still not configured so it can’t be used yet
 Configured
 Device has passed the addressed state and has been configured
 All functions may be used at this time
There are different device states defined in the USB specification. Take a minute to
familiarize yourself with those outlined here.