I've been trying to find some free and working code on the net about how to send and receive data (or frames as its seemed to be called) to and from a specific USB device by using VID and PID.
Does anybody know how to do this in delphi?
There seems to be nothing about this for delphi, at all!
See Robert Marquardt's HID controller suite for Delphi.
It will give you communication possibilities with a USB device. This unit is incorporated in Project Jedi as well.
See also Jan Axelson's HID page for examples. I think he has written book also. USB Complete. On his page are som Delphi references.
If you are using Delphi 2009 or newer, follow the link given in the answer on SO question :using-hidcontroller-on-delphi-2010
来源：https://stackoverflow.com/questions/9360527/data-exchange-directy-to-usb-device-with-vid-and-pid-in-delphi