>We have a software that accesses the diabetes glucose meters via a serial port.
>Now they are introducing a new meter that has a USB connection. The way to access the meters needs to be done enumerating the USB devices and recognizing the meter by its device ID.
>
>I looked around for code that does the enumeration, but nothing that can simply be used in a VFP application.
>
>I wonder if there is an API or another third party interface that I could use in VFP?

If it is just the device id that you need, maybe something like this can give you a starting point:

clear
loLocator			= CREATEOBJECT('WBEMScripting.SWBEMLocator')
loWMI				= loLocator.ConnectServer()
loDevices			= loWMI.ExecQuery('Select * from Win32_USBControllerDevice')

for each loDevice in loDevices
	try
		loDependent			= GETOBJECT("winmgmts:" + loDevice.Dependent)
		? loDependent.Status, 'DeviceID: ', loDependent.DeviceID, 'Description: ', loDependent.Description, loDependent.Name
	catch to loException
		? 'Exception: ', loException.Message
	endtry
endfor