Usb Suspend Mode; Usb Resume Mode - Sierra Wireless AirPrime SL808 Series Product Technical Specification & Customer Design Manuallines

Product Technical Specification & Customer Design Guidelines
46 Proprietary and Confidential - Specifications subject to change
4.7.4.1 Supported architectures
The AirPrime SL808X Embedded Module supports the following architectures
over the USB interface on Windows, Windows CE, and Linux systems:
• Sierra Wireless Direct IP—Composite USB
• Non-MUX—Composite USB
• MUX (3GPP 27.010)—Composite USB (The MUX architecture is also
available over the UART interface.)
• Non-MUX—Non-composite USB
For design requirements, see [6] AirCard/AirPrime USB Driver Developer's
Guide.
The basic service configuration is PRI-dependent and may include the NDIS, AT,
and CnS services. The advanced service configuration (available for Windows
and Windows CE) is disabled by default, and may include the DM and PDP
services.
4.7.4.2 USB driver requirements
The host USB driver must meet each of these requirements:
• Must act as a USB host device to interface with the module.
• Must support remote wakeup, resume, and suspend operations as described
in Universal Serial Bus Specification, Rev 2.0, and
page 46 and

USB Resume mode

• Must support serial port emulation. The module implements both 27.010
multiplexing and USB-CDC.
• Should NOT send any SOF tokens (start-of-frames) to the module when there
is no valid data to send. These tokens keep the module awake and cause
unnecessary power consumption.

4.7.5 USB Suspend mode

When the module enters suspend mode, it shuts down the USB clock to save
power.
While in the suspend state:
• Module provides signalling on the USB interface (USB_D+/USB_D-) to
indicate its current state to the host device.
• VCC_3V6 must be maintained.
4.7.6 USB Resume mode
USB activity may be resumed by either the USB host or by the module:
• Host-initiated:
a. USB transceiver detects the change in bus activity and triggers the
USB_RESUME interrupt to the module's processor.
b. Module enables its USB clock and responds to the host.
USB Suspend mode
on page 46.
on
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