558
11054A–ATARM–27-Jul-11
SAM9X25
558
11054A–ATARM–27-Jul-11
SAM9X25
33.6.13
Power Modes
33.6.13.1
Controlling Device States
A USB device has several possible states. Refer to Chapter 9 (USB Device Framework) of the
Universal Serial Bus Specification, Rev 2.0.
Figure 33-20.
UDPHS Device State Diagram
Movement from one state to another depends on the USB bus state or on standard requests
sent through control transactions via the default endpoint (endpoint 0).
After a period of bus inactivity, the USB device enters Suspend Mode. Accepting Sus-
pend/Resume requests from the USB host is mandatory. Constraints in Suspend Mode are very
strict for bus-powered applications; devices may not consume more than 500 μA on the USB
bus.
While in Suspend Mode, the host may wake up a device by sending a resume signal (bus activ-
ity) or a USB device may send a wake-up request to the host, e.g., waking up a PC by moving a
USB mouse.
The wake-up feature is not mandatory for all devices and must be negotiated with the host.
Attached
Suspended
Suspended
Suspended
Suspended
Hub Reset
or
Deconfigured
Hub
Configured
Bus Inactive
Bus Activity
Bus Inactive
Bus Activity
Bus Inactive
Bus Activity
Bus Inactive
Bus Activity
Reset
Reset
Address
Assigned
Device
Deconfigured
Device
Configured
Powered
Default
Address
Configured
Power
Interruption
Summary of Contents for SAM9X25
Page 26: ...26 11054A ATARM 27 Jul 11 SAM9X25...
Page 138: ...138 11054A ATARM 27 Jul 11 SAM9X25 138 11054A ATARM 27 Jul 11 SAM9X25...
Page 162: ...162 11054A ATARM 27 Jul 11 SAM9X25 162 11054A ATARM 27 Jul 11 SAM9X25...
Page 216: ...216 11054A ATARM 27 Jul 11 SAM9X25 216 11054A ATARM 27 Jul 11 SAM9X25...
Page 266: ...266 11054A ATARM 27 Jul 11 SAM9X25 266 11054A ATARM 27 Jul 11 SAM9X25...
Page 330: ...330 11054A ATARM 27 Jul 11 SAM9X25 330 11054A ATARM 27 Jul 11 SAM9X25...
Page 374: ...374 11054A ATARM 27 Jul 11 SAM9X25...
Page 468: ...468 11054A ATARM 27 Jul 11 SAM9X25 468 11054A ATARM 27 Jul 11 SAM9X25...
Page 532: ...532 11054A ATARM 27 Jul 11 SAM9X25 532 11054A ATARM 27 Jul 11 SAM9X25...
Page 692: ...692 11054A ATARM 27 Jul 11 SAM9X25 692 11054A ATARM 27 Jul 11 SAM9X25...
Page 777: ...777 11054A ATARM 27 Jul 11 SAM9X25 777 11054A ATARM 27 Jul 11 SAM9X25...
Page 886: ...886 11054A ATARM 27 Jul 11 SAM9X25 886 11054A ATARM 27 Jul 11 SAM9X25...
Page 962: ...962 11054A ATARM 27 Jul 11 SAM9X25 962 11054A ATARM 27 Jul 11 SAM9X25...
Page 1036: ...1036 11054A ATARM 27 Jul 11 SAM9X25 1036 11054A ATARM 27 Jul 11 SAM9X25...
Page 1128: ...1128 11054A ATARM 27 Jul 11 SAM9X25 1128 11054A ATARM 27 Jul 11 SAM9X25...
Page 1130: ...1130 11054A ATARM 27 Jul 11 SAM9X25...
Page 1132: ...1132 11054A ATARM 27 Jul 11 SAM9X25...
Page 1144: ...xii 11054A ATARM 27 Jul 11 SAM9X25...