Download CTS Port Devices Driver

Posted By admin On 30/01/22
Google is committed to advancing racial equity for Black communities. See how.

Aug 16, 2015 All this devices use a PL2303 to provide a connection to an USB port, but inside, they are RS232-like interface build (and appear as a COM port in your operating system). When you plug the device into USB, it is well recognized by W10 and it try to load the Prolific driver. Device refers to the Android device. Peripheral refers to an external USB audio peripheral connected to the Android device. Mandated peripherals. For the USB audio CTS Verifier Tests to know the attributes and capabilities they are verifying, it is necessary to specify a set of known peripherals to test against. Download DSA's MTTTY - An easy to use application that allows you to quickly connect to a COM port in order to monitor the performance of the attached device. CTS, DSR changes, breaks, ring. When autocomplete results are available use up and down arrows to review and enter to select.

Android 4.2 R4 Compatibility Test Suite (CTS) Android 4.2 R5 CTS Verifier; Android 4.1. Android 4.1 is the release of the development milestone code-named Jelly Bean. The source code of the Compatibility Test Suite revisions below is available at the 'android-cts-4.1r4' tag in the open source tree. Android 4.1 R4 Compatibility Test Suite (CTS).

TheWi-Fi Aware feature added in Android 8.0 enables supporting devices to discover, connect,and range (added in Android 9) to one another directlyusing the Wi-Fi Aware protocol without internet or cellular network access. Thisfeature, built upon the Wi-Fi Alliance (WFA)Wi-Fi Aware specification (versions 2.0 and 3.0), allows easy sharing of high-throughput data amongtrusted devices and apps that are otherwise off-network.

Examples and source

To use this feature, device manufacturers should implement the Wi-FiHardware Interface Design Language (HIDL) providedin the Android Open Source Project (AOSP). HIDL replaces the previousHardware Abstraction Layer (HAL) structure used tostreamline implementations by specifying types and method calls collected intointerfaces and packages.

Follow the Wi-Fi HIDL to employ the Wi-Fi Aware feature:hardware/interfaces/wifi/1.2 or higher. The Wi-Fi Aware HAL surface is verylarge; thehardware/interfaces/wifi/1.2/ file describes the subset that is currently in use by the framework.

Download Cts Port Devices Driver License

You can reference the legacy Wi-Fi HAL to see how it correlates with the newHIDL interface:hardware/libhardware_legacy/+/master/include/hardware_legacy/wifi_nan.h.


Device manufacturers need to provide both framework and HAL/firmware support:

  • Framework:
    • AOSP code
    • Enable Aware: Requires both a feature flag and an HIDL build flag
  • Wi-Fi Aware (NAN) HAL support (which implies firmware support)

To implement this feature, device manufacturers implement the Wi-Fi HIDL andenable two feature flags:

  • In or located indevice/<oem>/<device>, add the following flag:

  • In located in device/<oem>/<device>, modify thePRODUCT_COPY_FILES environment variable to include support for the Wi-FiAware feature:

Wi-Fi Aware includes ranging to peer devices using the IEEE 802.11mc protocol,also known as Round Trip Time (RTT). This sub-feature of Wi-Fi Aware isconditional on the device supporting the Wi-Fi RTT feature, that is, it requiresthe device to support both Wi-Fi Aware and Wi-Fi RTT. For more details, seeWi-Fi RTT.

Otherwise, everything required for this feature is included in AOSP.

The WIFI_HIDL_FEATURE_AWARE flag is ignored if theWIFI_HAL_INTERFACE_COMBINATIONSflag is specified. For more information, seeWi-Fi multi-interface concurrency.

MAC randomization

Android requires the MAC address of the Wi-Fi Aware discovery (NMI) and datainterfaces (NDPs) to be randomized and not be identical to the true MAC addressof the device. The MAC addresses must be:

  • Randomized whenever Wi-Fi Aware is enabled or re-enabled.
  • When Wi-Fi Aware is enabled, the MAC address must be randomized at a regularinterval configured by theNanConfigRequest.macAddressRandomizationIntervalSec HIDL parameter. Thisis configured by the framework by default to be 30 minutes.

    Note: Per the Wi-Fi Aware spec, randomization may be suspended while an NDPis configured. Suspension does not imply that the factory MAC address isused (it must never be used for Wi-Fi Aware), but that the MAC addressis re-randomized less frequently than otherwise required.

Download Cts Port Devices Driver Download


Android provides a set of unit tests, integration tests (ACTS),Compatibility Test Suite (CTS) tests, andCTS Verifier tests to validate the Wi-Fi Awarefeature. Wi-Fi Aware can also be tested using theVendor Test Suite (VTS).

Unit tests

The Wi-Fi Aware package tests are executed using:

Service tests:

Manager tests:

Integration tests (ACTS)

The acts/sl4a test suite, described intools/test/connectivity/acts/tests/google/wifi/aware/, providesfunctional, performance, and stress tests.

Compatibility Test Suite (CTS) tests

Use CTS tests to validate the Wi-Fi Aware feature. CTS detects when the featureis enabled and automatically includes the associated tests.

The CTS tests can be triggered using:

CTS Verifier tests

CTS Verifier tests validate Wi-Fi Aware behavior using two devices: a testdevice and a known good device. To run the tests, open CTS Verifier andnavigate to the section titled Wi-Fi Aware Tests.


Versions supported

  • Windows 10
  • Windows 8.1

Applies to

  • Device manufacturers of CDC Control devices

Microsoft-provided in-box driver (Usbser.sys) for your Communications and CDC Control device.


In Windows 10, the driver has been rewritten by using the Kernel-Mode Driver Framework that improves the overall stability of the driver.

  • Improved PnP and power management by the driver (such as, handling surprise removal).
  • Added power management features such as USB Selective Suspend.

In addition, UWP applications can now use the APIs provided by the new Windows.Devices.SerialCommunication namespace that allow apps to talk to these devices.

Usbser.sys installation

Load the Microsoft-provided in-box driver (Usbser.sys) for your Communications and CDC Control device.


If you trying to install a USB device class driver included in Windows, you do not need to download the driver. They are installed automatically. If they are not installed automatically, contact the device manufacturer. For the list of USB device class driver included in Windows, see USB device class drivers included in Windows.

Windows 10

In Windows 10, a new INF, Usbser.inf, has been added to %Systemroot%Inf that loads Usbser.sys as the function device object (FDO) in the device stack. If your device belongs to the Communications and CDC Control device class, Usbser.sys is loaded automatically.You do not need to write your own INF to reference the driver. The driver is loaded based on a compatible ID match similar to other USB device class drivers included in Windows.



  • If you want to load Usbser.sys automatically, set the class code to 02 and subclass code to 02 in the Device Descriptor. For more information, see USB communications device class. With this approach, you are not required to distribute INF files for your device because the system uses Usbser.inf.
  • If your device specifies class code 02 but a subclass code value other than 02, Usbser.sys does not load automatically. Pnp Manager tries to find a driver. If a suitable driver is not found, the device might not have a driver loaded. In this case, you might have to load your own driver or write an INF that references another in-box driver.
  • If your device specifies class and subclass codes to 02, and you want to load another driver instead of Usbser.sys, you have to write an INF that specifies the hardware ID of the device and the driver to install. For examples, look through the INF files included with sample drivers and find devices similar to your device. For information about INF sections, see Overview of INF Files.


Microsoft encourages you to use in-box drivers whenever possible. On mobile editions of Windows, such as Windows 10 Mobile, only drivers that are part of the operating system are loaded. Unlike desktop editions, it is not possible to load a driver through an external driver package. With the new in-box INF, Usbser.sys is automatically loaded if a USB-to-serial device is detected on the mobile device.

Windows 8.1 and earlier versions

In Windows 8.1 and earlier versions of the operating system, Usbser.sys is not automatically loaded when a USB-to-serial device is attached to a computer. To load the driver, you need to write an INF that references the modem INF (mdmcpq.inf) by using the Include directive. The directive is required for instantiating the service, copying inbox binaries, and registering a device interface GUID that applications require to find the device and talk to it. That INF specifies 'Usbser' as a lower filter driver in a device stack.

The INF also needs to specify the device setup class as Modem to use mdmcpq.inf. Under the [Version] section of the INF, specify the Modem and the device class GUID. for details, see System-Supplied Device Setup Classes.

For more information, see this KB article.

Configure selective suspend for Usbser.sys

Starting in Windows 10, Usbser.sys supports USB Selective Suspend. It allows the attached USB-to-serial device to enter a low power state when not in use, while the system remains in the S0 state. When communication with the device resumes, the device can leave the Suspend state and resume Working state. The feature is disabled by default and can be enabled and configured by setting the IdleUsbSelectiveSuspendPolicy entry under this registry key:

To configure power management features of Usbser.sys, you can set IdleUsbSelectiveSuspendPolicy to:

  • '0x00000001': Enters selective suspend when idle, that is, when there are no active data transfers to or from the device.

  • '0x00000000': Enters selective suspend only when there are no open handles to the device.

That entry can be added in one of two ways:

  • Write an INF that references the install INF and add the registry entry in the HW.AddReg section.

  • Describe the registry entry in an extended properties OS feature descriptor. Add a custom property section that sets the bPropertyName field to a Unicode string, 'IdleUsbSelectiveSuspendPolicy' and wPropertyNameLength to 62 bytes. Set the bPropertyData field to '0x00000001' or '0x00000000'. The property values are stored as little-endian 32-bit integers.

    For more information, see Microsoft OS Descriptors.

Develop Windows applications for a USB CDC device

If you install Usbser.sys for the USB CDC device, here are the application programming model options:

  • Starting in Windows 10, a Windows app can send requests to Usbser.sys by using the Windows.Devices.SerialCommunication namespace. It defines Windows Runtime classes that can use to communicate with a USB CDC device through a serial port or some abstraction of a serial port. The classes provide functionality to discover such serial device, read and write data, and control serial-specific properties for flow control, such as setting baud rate, signal states.

  • In Windows 8.1 and earlier versions, you can write a Windows desktop application that opens a virtual COM port and communicates with the device. For more information, see:

    Win32 programming model:

    • .NET framework programming model:

Related topics