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USB Device Controller
Table 40. Device Status Register (DEVSTAT) (Continued)
Bit
Name
7
A_ALT_HNP_SUPPORT
6
R_WK_OK
5
USB_RESET
84
Universal Serial Bus (USB)
Description
The B-device is connected to an A-device port that is not capable of
HNP, but the A-device has an alternate port that is capable of HNP.
This A_ALT_HNP_SUPPORT bit is used for On-The-Go feature
selection purposes. See the On-The-Go Supplement to the USB 2.0
Specification.
0: Not significant
1: B-device connection to not HNP capable A-device
Value after MPU or USB reset is low.
The remote wake-up granted bit is automatically set and cleared
when the core receives a valid set/clear device feature request from
the USB host. It returns a 1 when the USB host grants the function
the ability to assert remote wake-up.
0: Not significant
1: Remote wake-up granted
Value after MPU or USB reset is low.
USB reset signaling is active. The USB_RESET bit returns 1 when
the USB host resets the USB bus. A valid USB reset resets the
endpoint FIFOS, the other control register bits, except for
SYSCON1.CFG_LOCK and the associated configuration registers
(0x20 to 0x3F), IRQ_EN.DS_CHG_IE and IRQ_SRC.DS_CHG, and
forces the device to the default state for DEVSTAT (this register).
This bit is cleared at the end of reset.
This bit, as well as other DEVSTAT bits, is double-buffered. If a
pending interrupt has not been handled when a USB reset occurs
and is handled only when USB reset is finished, the USB device
controller does not see the USB_RESET bit going high and then
low.
0: Device is not being reset by USB host.
1: Device is being reset by USB host.
The value after the USB device controller hardware reset is low, and
during USB reset is high (low after USB reset).
SPRU761A
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