viUsbControlIn/Out parameters

[MariaGil]

Hi:

I have write a program in CVI/Labwindows for talk with a pendrive connected in a usb port in my computer. I can read a lot of parameters with the function viGetAttribute and the correponding attribute like VI_ATTR_USB_NUM_PIPES for obtain the number of pipes availables.

My problem is that I don't know what are the parameters that use the function viUsbControlIn. In the "Recall Function Panel" there isn't a full explanation of this. The parameters that I don't know are:

bmRequestType

bRequestType

wValue

wIndex

Sorry for my english and thank you.

[AitziberH]

You can find more info about these parameters in the USB Specification, and the following links could help as well:

http://www.beyondlogic.org/usbnutshell/usb5.htm

http://zone.ni.com/devzone/cda/epd/p/id/3635