Online Development Notebook > Index > ODN > USBm DLL Programming > DLL Commands > FindDevices

FindDevices

Description:

This is a USBm.dll function that scans all of the HID devices available on the bus. If a device qualifies as a U4xx, then open access to the device and place the device into the internal data structure for U4xx devices. Devices are indexed with a device number starting from 0 to the number of devices found minus one. This function is the initial call to connect devices logically to the PC. Once this function is called (successfully) then access to the device can be done with the device commands.

 

Command Syntax:

true⁄false USBm_FindDevices()

The USBm_FindDevices function syntax has these parts:

Part Description
  No argument

 

Remarks:

Note: USBm_FindDevices returns FALSE for no connected devices, otherwise the return value is TRUE.

 

VB Declaration (USBmAPI.bas)

Public Declare Function USBm_FindDevices _
    Lib "USBm.dll" _
        () _
    As Integer

 

VB Example

Dim result As Integer

    result = USBm_FindDevices

This code fragment shows that result is loaded with TRUE if devices exist and can be opened by the DLL, or with FALSE.

 

C Example

-TBD-

Hardware:  U401 USB Interface    U421 USB Interface
Programming:  USBm DLL Programming    Download Files
Application Notes:  U4x1 Application Notes    Misc Applications and Information    FAQ