Register Descriptions
1319
SPRUH22I – April 2012 – Revised November 2019
Copyright © 2012–2019, Texas Instruments Incorporated
M3 Universal Serial Bus (USB) Controller
18.5.13 USB Device Control Register (USBDEVCTL), offset 0x060
The USB device control 8-bit register (USBDEVCTL) is used for controlling and monitoring the USB VBUS
line. If the PHY is suspended, no PHY clock is received and the VBUS is not sampled. In addition, in Host
mode, USBDEVCTL provides the status information for the current operating mode (Host or Device) of the
USB controller. If the USB controller is in Host mode, this register also indicates if a full- or low-speed
Device has been connected.
Mode(s):
OTG A or Host
USBDEVCTL is shown in
and described in
.
Figure 18-18. USB Device Control Register (USBDEVCTL)
7
6
5
4
3
2
1
0
DEV
FSDEV
LSDEV
VBUS
HOSTMODE
HOSTREQ
SESSION
R-1
R-0
R-0
R-0
R-0
R/W-0
R/W-0
LEGEND: R/W = Read/Write; R = Read only; -
n
= value after reset
Table 18-21. USB Device Control Register (USBDEVCTL) Field Descriptions
Bit
Field
Value
Description
7
DEV
Device mode
0
The USB controller is operating on the OTG A side of the cable.
1
The USB controller is operating on the OTG B side of the cable.
Only valid while a session is in progress.
6
FSDEV
Full-Speed Device Detected
0
A full-speed Device has not been detected on the port.
1
A full-speed Device has been detected on the port.
5
LSDEV
Low-Speed Device Detected
0
A low-speed Device has not been detected on the port.
1
A low-speed Device has been detected on the port.
4-3
VBUS
0-3h
These read-only bits encode the current VBus level as follows:
0
Below Session End. VBUS is detected as under 0.5 V.
1h
Above Session End, below AValid. VBUS is detected as above 0.5 V and under 1.5 V.
2h
Above AValid, below VBusValid. VBUS is detected as above 1.5 V and below 4.75 V.
3h
Above VBusValid. VBUS is detected as above 4.75 V.
2
HOSTMODE
This read-only bit is set when the USB controller is acting as a Host.
0
The USB controller is acting as a Device.
1
The USB controller is acting as a Host.
Only valid while a session is in progress.
1
HOSTREQ
When set, the USB controller will initiate the Host Negotiation when Suspend mode is entered. It is
cleared when Host Negotiation is completed.
0
No effect
1
Initiates the Host Negotiation when SUSPENDmode is entered.