EFM32WG Datasheet, PDF (323/834 Pages) List of Unclassifed Manufacturers – The EFM32WG Wonder Gecko is the ideal choice for demanding 8-, 16-, and 32-bit energy sensitive applications.

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Figure 15.32. SRP Detection by Core When Operating as A-device
Host m ode (PHY
not driving VBUS)
Program USB_GINTMSK.
(Unm ask OTGINT, MODEMIS,
SESSREQINT)
If host’s application decides to
t urn on VBUS volunt arily,
then the application need
not wait for SRP from
d e v .i c e
No
No
Int errupt?
Yes
Read USB_GINTSTS
GINTSTS.
SESSREQINT = 1 ?
Yes
Host Init ializat ion St eps. Refer t o t he Host
Initialization section of this chapter for
more information.
(In t his st ep t he OTG FSM is in a_host
st at e.)
Not e: If MODEMIS int errupt
is detected during this
process, it m eans t hat t he
connector has been
plugged out or
int erchange.d This can be
confirmed by reading
USB_GINTSTS.CONIDSTSCHNG
Host Transact ions
Figure 15.33 (p. 324) illustrates the steps that need to be performed by B-device’s application (core
as B-device) in order to establishing a connection with A-device by signaling a SRP.
2013-05-08 - Wonder Gecko Family - d0233_Rev0.50
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