13.25.6.2.4 USB Reset

The USB bus reset is initiated by a connected host and managed by hardware.

During USB reset the following registers are cleared:

Device Endpoint Configuration (EPCFG) register - except for Endpoint 0
Device Frame Number (FNUM) register
Device Address (DADD) register
Device Endpoint Interrupt Enable Clear/Set (EPINTENCLR/SET) register
Device Endpoint Interrupt Flag (EPINTFLAG) register
Transmit Stall 0 bit in the Endpoint Status register (EPSTATUS.STALLRQ0)
Transmit Stall 1 bit in the Endpoint Status register (EPSTATUS.STALLRQ1)
Endpoint Interrupt Summary (EPINTSMRY) register
Upstream resume bit in the Control B register (CTRLB.UPRSM)

At the end of the reset process, the End of Reset bit is set in the Interrupt Flag register (INTFLAG.EORST).

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