u-blox LARA-R2 series System Integration Manual Download

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LARA-R2 series - System Integration Manual

UBX-16010573 - R02

Objective Specification

System description

Page 48 of 148

1.9.2.2

USB in Windows

USB drivers are provided for Windows operating system platforms and should be properly installed / enabled by
following the step-by-step instructions available in the

EVK-R2xx User Guide

[3] or in the

Windows Embedded

OS USB Driver Installation Application Note

[4].

USB drivers are available for the following operating system platforms:



Windows 7



Windows 8



Windows 8.1



Windows 10



Windows Embedded CE 6.0



Windows Embedded Compact 7



Windows Embedded Compact 2013

The module firmware can be upgraded over the USB interface by means of the FOAT feature, or using the u-blox
EasyFlash tool (for more details see

Firmware Update Application Note

[23].

1.9.2.3

USB in Linux/Android

It is not required to install a specific driver for each Linux-based or Android-based operating system (OS) to use
the module USB interface, which is compatible with standard Linux/Android USB kernel drivers.
The full capability and configuration of the module USB interface can be reported by running “lsusb –v” or an
equivalent command available in the host operating system when the module is connected.

1.9.2.4

USB and power saving

The modules automatically enter the USB suspended state when the device has observed no bus traffic for a
specific time period according to the

USB 2.0 specifications

[9]. In suspended state, the module maintains any

USB  internal  status  as  device.  In  addition,  the  module  enters  the  suspended  state  when  the  hub  port  it  is
attached to is disabled. This is referred to as USB selective suspend.
If the USB is suspended and a power saving configuration is enabled  by the AT+UPSV command, the module
automatically enters the low power idle-mode whenever possible but it wakes up to active-mode according to
any required activity related to the network (e.g. the periodic paging reception described in section 1.5.1.4) or
any other required activity related to the functions / interfaces of the module.
The USB exits suspend mode when there is bus activity. If the USB is connected and not suspended, the module
is  kept  ready  to  communicate  over  USB  regardless  the  AT+UPSV  settings,  therefore  the  AT+UPSV  settings  are
overruled but they have effect on the power saving configuration of the other interfaces (see 1.9.1.4).
The modules are capable of USB remote wake-up signaling: i.e. it may request the host to exit suspend mode or
selective  suspend  by  using  electrical  signaling  to  indicate  remote  wake-up,  for  example  due  to  incoming  call,
URCs, data reception on a socket. The remote wake-up signaling notifies the host that it should resume from its
suspended mode, if necessary, and service the external event. Remote wake-up is accomplished using electrical
signaling described in the

USB 2.0 specifications

[9].

For the module current consumption description with power saving enabled and USB suspended, or with power
saving disabled and USB not suspended, see sections 1.5.1.4, 1.5.1.5 and

LARA-R2 series Data Sheet

[1].

The additional

VUSB_DET

input pin available on LARA-R2 series modules provides the complete bus detach

functionality: the modules disable the USB interface when a low logic level is sensed after a high-to-low logic
level transition on the

VUSB_DET

input pin. This allows a further reduction of the module current consumption,

in particular as compared to the USB suspended status during low-power idle mode with power saving enabled.