HS_USB 2.0 device
RM0082
494/844
Doc ID 018672 Rev 1
23.8.6 Device
status
register
The device status is a RO register which echoes status information needed to service some
of the interrupts. The device status register bit assignments are given in
.
[02]
1'h0
DMA receive.
Setting this bit, the receive DMA is enabled.
[01]
Reserved
-
Read: undefined. Write: should be zero.
[00]
RES
1'h0
Resuming signaling on the USB.
This bit is used by the software application to perform a
remote wake-up resume. Setting this bit, the UDC-AHB
subsystem signals the USB host to resume the USB bus.
however, the application must first set RWKP bit in the
device configuration register, (indicating that the UDC-AHB
subsystem supports the remote wake-up feature), and the
USB host must already have issued a set feature request to
enable the device’s remote wake-up feature.
1.
Field supported in DMA mode only.
Table 401.
Device control register bit assignments (continued)
Bit
Name
Reset value
Description
Table 402.
Device status register bit assignments
Bit
Name
Reset value Description
[31:18]
TS
14’h0000
Frame number of the received SOF.
This 14 bit field indicates the frame number of the received
SOF, according to the following rules:
High-Speed (HS) operation
[31:21] = Millisecond frame number.
[20:18] = Microframe number
Full-Speed (FS) operation
[31:29] = Reserved.
[28:18] = Millisecond frame number.
[17]
Reserved
-
Read: undefined. Write: should be zero.
[16]
PHY
ERROR
1'h0
PHY Error.
This bit is set when either the phy_rxvalid or phy_rxactive
input signal is detected to be continuously asserted for 2 ms.
It results that the UDC-AHB subsystem goes to the suspend
state. When the application serves the early suspend
interrupt (ES bit of the device interrupt register,
interrupt register on page 495
) it also must check this bit to
determine if the early suspend interrupt was generated due to
PHY error detection.
Note: This bit is reserved for the UDC11-AHB subsystem.