NUMICRO-SDK Nuvoton Technology Corporation of America, NUMICRO-SDK Datasheet - Page 218

• Manufacturer Part Number: NUMICRO-SDK
• Description: KIT EVAUATION NUC100/120/130/140
• Manufacturer: Nuvoton Technology Corporation of America
• Series: NuMicro™r
• Type: MCUr

Specifications of NUMICRO-SDK

• Contents: Board, Cable, CD, Nu-Link
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: NUC100, NUC120, NUC130, NUC140

5.4.4.5
5.4.4.6
This USB provides 1 interrupt vector with 4 interrupt events (WAKEUP, FLDET, USB and BUS).
The WAKEUP event is used to wake up the system clock when the power down mode is enabled.
(The power mode function is defined in system power down control register, PWRCON). The
FLDET event is used for USB plug-in or unplug. The USB event notifies users of some USB
requests, like IN ACK, OUT ACK etc., and the BUS event notifies users of some bus events, like
suspend, resume, etc. User must set related bits in the interrupt enable register (USB_INTEN) of
USB Device Controller to enable USB interrupts.
Wakeup interrupt is only present when the chip entered power down mode and then wakeup
event had happened. After the chip enters power down mode, any change on USB_DP, USB_DM
and floating detect pin can wake up this chip (provided that USB wakeup function is enabled). If
this change is not intentionally, for example, a noise on floating detect pin, no interrupt but
wakeup interrupt will occur. After USB wakeup, this interrupt will occur when no other USB
interrupt events are present for more than 20ms. The following figure is the control flow of wakeup
interrupt.
USB interrupt is used to notify users of any USB event on the bus, and a user can read EPSTS
(USB_EPSTS[25:8]) and EPEVT5~0 (USB_INTSTS[21:16]) to know what kind of request is to
which endpoint and take necessary responses.
Same as USB interrupt, BUS interrupt notifies users of some bus events, like USB reset,
suspend, time-out, and resume. A user can read USB_ATTR to acknowledge bus events.
USB turns off PHY transceiver automatically to save power while this chip enters power down
Interrupt
Power Saving
NuMicro™ NUC100 Series Technical Reference Manual
Figure 5-10 Wakeup Interrupt Operation Flow
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Publication Release Date: Dec. 22, 2010
Revision V1.06