Drivers National Multifunction Devices


I want to control a stepper motor drive (step/direction) using the digital output on my USB DAQ and I have connected all the necessary wiring, so how do I control the motor for some simple moves in LabVIEW? Select Tape drivers and software for the Tape systems menu. Select Tape device drivers for the Tape drivers and software menu. Select your operating system for the Platform menu. It is recommended that you install the most current driver available. In these configurations, the Toaster device is a child device on the multifunction device, and the multifunction device is a child device on a PCMCIA bus. The INF file and installers for the Toaster device install the Serial driver as lower-level device filter driver to provide a 16550 UART-compatible interface for the Toaster device. Evaluating One Screen/One Control Multifunction Devices in Vehicles Multifunction in-vehicle information systems are becoming increasingly prevalent in cars. These systems typically use a centrally located display and a single control device to carry out a variety of operations including navigation, communications, entertainment, and climate.

A multifunction device occupies one location on its parent bus but contains more than one function. Combination printer/scanner/fax devices and modem/network cards are common multifunction devices.

In a multifunction device, the individual functions are independent. This means the functions must have the following characteristics:

  • The functions cannot have start-order dependencies.

  • The resource requirements for one function cannot be expressed in terms of the resources of another function (for example, function1 uses I/O port x and function2 uses port x + 200).

  • Each function must be able to operate as a separate device, even if it is serviced by the same drivers as another function.

  • Each function on the device must be enumerated.

  • Resource requirements for each function must be communicated to the PnP manager.

  • There must be INF files and drivers for each function.

The component responsible for each of these tasks depends on the multifunction standard for the device's parent bus, the extent to which the device conforms to the standard, and the capabilities of the parent bus driver.

If the device complies with the multifunction standards for its bus, your driver requirements are significantly reduced. Industry-wide multifunction standards have been defined for the PC Card and PCI buses.

If you are working with a multifunction DVD/CD-ROM device used for data storage (not for audio/video playback), you should use the system-supplied WDM DVD class driver, which treats the device as a single logical unit.

For a multifunction device that combines other functionality, you can use a system-supplied driver and INF file if the device complies with the multifunction standards for its bus. The system supplied multifunction driver (mf.sys) can handle the bus-level enumeration and resource allocation requirements for the device, and the system-supplied INF (mf.sys) can install the multifunction device. You need to supply only a function driver and INF file for each of the individual device functions.


If the device does not comply with the standard for its bus, you might need to supply a driver equivalent to mf.sys in functionality, in addition to function drivers and INF files for the device functions.

To install a multifunction device, you typically provide a base INF file for the device and an additional INF file for each of the device's functions. The base INF file typically copies the INF files for the device's individual functions. For information about how to accomplish this, see Copying INFs.

The following sections describe driver and installation requirements for various types of multifunction devices:

See INF File Sections and INF File Directives for information about INF file syntax.

The Windows Driver Kit (WDK) includes a separate section that describes how to support multifunction audio devices.


The PC Card multifunction standard specifies that a multifunction device has a set of configuration registers in attribute memory for each function. These registers allow the PCMCIA bus driver to, for example, enable each function independently and define a range of I/O resources that are exclusive to each function. The standard also specifies that a multifunction device contains, in attribute memory, the address of each set of configuration registers. These addresses enable the PCMCIA bus driver to program the configuration registers.

Drivers National Multifunction Devices Bluetooth

If a 16-bit PC Card device implements the PC Card multifunction standard completely and correctly, the vendor of such a device has minimal INF and driver requirements to ensure that the device is configured properly on an NT-based system. See Supporting PC Cards That Conform to the Multifunction Standard for more information.

If a 16-bit PC Card device does not fully implement the PC Card multifunction standard, the vendor must provide the missing information in an INF file. There are two ways that a multifunction PC Card device might fail to implement the multifunction standard:

  1. The device implements a set of multifunction configuration registers per function but does not contain the locations of all sets of registers in its attribute memory.

  2. The device does not implement a set of multifunction configuration registers per function.

If a device has the limitations listed above, the PCMCIA bus driver can program the configuration registers if the device's INF has the necessary information in DDInstall.LogConfigOverride section(s). See the following sections for further information:

Drivers National Multifunction Devices

Drivers National Multifunction Devices Scanner

Cardbus devices essentially follow the PCI multifunction rules. See Supporting Multifunction PCI Devices.