Registers
1710
SPRUH82C – April 2013 – Revised September 2016
Copyright © 2013–2016, Texas Instruments Incorporated
Universal Serial Bus 2.0 (USB) Controller
34.4.22 Power Management Register (POWER)
The power management register (POWER) is shown in
and described in
.
Figure 34-48. Power Management Register (POWER)
7
6
5
4
3
2
1
0
ISOUPDATE
SOFTCONN
HSEN
HSMODE
RESET
RESUME
SUSPENDM
ENSUSPM
R/W-0
R/W-0
R/W-1
R-0
R/W-0
R/W-0
R/W-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 34-52. Power Management Register (POWER) Field Descriptions
Bit
Field
Value
Description
7
ISOUPDATE
0-1
When set, the USB controller will wait for an SOF token from the time TxPktRdy is set before
sending the packet. If an IN token is received before an SOF token, then a zero length data packet
will be sent. Note: this is only valid in Peripheral Mode. This bit only affects endpoints performing
Isochronous transfers.
6
SOFTCONN
0-1
If Soft Connect/Disconnect feature is enabled, then the USB D+/D- lines are enabled when this bit
is set and tri-stated when this bit is cleared. Note: this is only valid in Peripheral Mode.
5
HSEN
0-1
When set, the USB controller will negotiate for high-speed mode when the device is reset by the
hub. If not set, the device will only operate in full-speed mode.
4
HSMODE
0-1
This bit is set when the USB controller has successfully negotiated for high-speed mode.
3
RESET
0-1
This bit is set when Reset signaling is present on the bus. Note: this bit is Read/Write in Host
Mode, but read-only in Peripheral Mode.
2
RESUME
0-1
Set to generate Resume signaling when the controller is in Suspend mode. The bit should be
cleared after 10 ms (a maximum of 15 ms) to end Resume signaling. In Host mode, this bit is also
automatically set when Resume signaling from the target is detected while the USB controller is
suspended.
1
SUSPENDM
0-1
In Host mode, this bit should be set to enter Suspend mode. In Peripheral mode, this bit is set on
entry into Suspend mode. It is cleared when the interrupt register is read, or the RESUME bit is set.
0
ENSUSPM
0-1
Set to enable the SUSPENDM output.