Bring up drivers. USB Function driver bring-up is only required if you support USB Function mode. If you previously implemented a USB Function driver for a USB micro-B connector, describe the appropriate connectors as USB Type-C in the ACPI tables for the USB Function driver to continue working. The pencil icon is used to RS-232-type devices do not work NOTE highlight important information. On the P400 communication port. The caution symbol indicates The unit is not waterproof or CAUTION hardware or software failure, or dustproof, and is intended for loss of data.
- If you need to update, rollback, uninstall, or install a driver, this device is what you need to modify. Once you’ve found the device, you should insert your SD card and then scan your hardware for changes. Your SD cad should show up and/or Windows 10 should install the correct drivers for it.
- The pencil icon is used to RS-232-type devices do not work NOTE highlight important information. On the P400 communication port. The caution symbol indicates The unit is not waterproof or CAUTION hardware or software failure, or dustproof, and is intended for loss of data.
This topic is intended for OEMs who want to build a Windows 10 system with USB Type-C connector and want to leverage OS features that allow for faster charging, power delivery, dual role, alternate modes, and error notifications through Billboard devices.
A traditional USB connection uses a cable with a USB A and USB B connector on each end. The USB A connector always plugs in to the host side and the USB B connector connects the function side, which is a device (phone) or peripheral (mouse, keyboard). By using those connectors, you can only connect a host to a function; never a host to another host or a function to another function. The host is the power source provider and the function consumes power from the host.
The traditional configuration limits some scenarios. For example, if a mobile device wants to connect to a peripheral, the device must act as the host and deliver power to the connected device.
The USB Type-C connector, introduced by the USB-IF, defined in the USB 3.1 specification, addresses those limitations. Windows 10 introduces native support for those features.
- Allows for faster charging up to 100W with Power Delivery over USB Type-C.
- Single connector for both USB Hosts and USB Devices.
- Can switch USB roles to support a USB host or device.
- Can switch power roles between sourcing and sinking power.
- Supports other protocols like DisplayPort and Thunderbolt over USB Type-C.
- Introduces USB Billboard device class to provide error notifications for Alternate Modes.
USB Type-C connector is reversible and symmetric.
The main component are: the USB Type-C connector and its port or PD controller that manages the CC pin logic for the connector. Such systems typically have a dual-role controller that can swap the USB role from host to function. It has Display-Out module that allows video signal to be transmitted over USB. Optionally it can support BC1.2 charger detection.
Consider recommendations for the design and development of USB components, including minimum hardware requirements, Windows Hardware Compatibility Program requirements, and other recommendations that build on those requirements.Hardware component guidelines USB
Choose a driver model
Use this flow chart to determine a solution for your USB Type-C system.
|If your system...||Recommended solution...|
|Does not implement PD state machines||Write a client driver to the UcmTcpciCx class extension.|
Write a USB Type-C port controller driver
|Implements PD state machines in hardware or firmware and support USB Type-C Connector System Software Interface (UCSI) over ACPI||Load the Microsoft provided in-box drivers, UcmUcsiCx.sys and UcmUcsiAcpiClient.sys.|
See UCSI driver.
|Implements PD state machines in hardware or firmware, but either does not support UCSI, or support UCSI but requires a transport other than ACPI||Write a client driver for the UcmCx class extension.|
Write a USB Type-C connector driver
Write a USB Type-C Policy Manager client driver
|Implements UCSI but requires a transport other than ACPI||Write a client driver to the UcmUcsiCx class extension.|
Use this sample template and modify it based on a transport that your hardware uses.
Write a UCSI client driver
Bring up drivers
USB Function driver bring-up is only required if you support USB Function mode. If you previously implemented a USB Function driver for a USB micro-B connector, describe the appropriate connectors as USB Type-C in the ACPI tables for the USB Function driver to continue working.
For more information, see instructions about writing a USB Function driver.
USB Role-Switch driver bring-up is only required for devices that have a Dual Role controller that assumes both Host and Function roles. To bring-up the USB Role-Switch driver, you need to modify the ACPI tables to enable the Microsoft in-box USB role-switch driver.
For more information, see the guidance for bringing up the USB Role Switch Driver.
A USB Connector Manager Driver is required for Windows to manage the USB Type-C ports on a system. The bring-up tasks for a USB Connector Manager driver depend on the driver that you choose for the USB Type-C ports: The Microsoft in-box UCSI (UcmUcsiCx.sys and UcmUcsiAcpiClient.sys) driver, a UcmCx client driver, or a UcmTcpciCx client driver. For more information, see the links in the preceding section that describe how to choose the right solution for your USB Type-C system.
Perform various functional and stress tests on systems and devices that expose a USB Type-C connector.
Test USB Type-C systems with USB Type-C ConnEx - Run USB tests included in the Windows Hardware Lab Kit (HLK) for Windows 10.
Run USB function HLK tests with a C-to-A cable (search for Windows USB Device in the HLK
Certification/ComplianceAttend Power Delivery and USB Type-C compliance workshops hosted by the standards bodies.
- Windows 10
- Windows 8.1
- 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.
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.
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.
Verifone Vx805 Usb Driver
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: