NUC970 Technical Reference Manual
Publication Release Date: Dec. 15, 2015
- 738 -
Revision V1.30
NUC97
0
T
E
CHNIC
A
L
RE
F
E
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CE
MA
NUA
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USB Port Status and Control Register (UPSCR)
Register
Offset
R/W
Description
Reset Value
UPSCR0
0x064
R/W
USB Port 0 Status and Control Register
0x0000_2000
UPSCR1
0x068
R/W
USB Port 1 Status and Control Register
0x0000_2000
31
30
29
28
27
26
25
24
Reserved
23
22
21
20
19
18
17
16
Reserved
PTC
15
14
13
12
11
10
9
8
Reserved
PO
PP
LSTS
Reserved
PRST
7
6
5
4
3
2
1
0
SUSPEND
FPR
OCC
OCA
PEC
PE
CSC
CCS
Bits
Description
[31:20]
Reserved
Reserved.
[19:16]
PTC
Port Test Control (R/W)
When this field is zero, the port is NOT operating in a test mode. A non-zero value
indicates that it is operating in test mode and the specific test mode is indicated by the spe-
cific value. The encoding of the test mode bits are (0x6 ~ 0xF are reserved):
Bits Test Mode
0x0 = Test mode not enabled.
0x1 = Test J_STATE.
0x2 = Test K_STATE.
0x3 = Test SE0_NAK.
0x4 = Test Packet.
0x5 = Test FORCE_ENABLE.
[15:14]
Reserved
Reserved.
[13]
PO
Port Owner (R/W)
This bit unconditionally goes to a 0b when the Configured bit in the CONFIGFLAG register
makes a 0 to 1 transition. This bit unconditionally goes to 1 whenever the Configured bit is
zero.
System software uses this field to release ownership of the port to a selected host
controller (in the event that the attached device is not a high-speed device). Software
writes a one to this bit when the attached device is not a high-speed device. A one in this
bit means that a companion host controller owns and controls the port.
[12]
PP
Port Power (PP)
Host controller has port power control switches. This bit represents the Current setting of
the switch (0 = off, 1 = on). When power is not available on a port (i.e. PP equals a 0), the
port is nonfunctional and will not report attaches, detaches, etc.
When an over-current condition is detected on a powered port and PPC is a one, the PP
bit in each affected port may be transitioned by the host controller from a 1 to 0 (removing
power from the port).