Usb pid and vid

AccordingUSB
According to the regulations, all USB devices have Supplier ID (Vid
And product identification code (PID
The host uses different vid and PID to distinguish different devices. Both vid and PID are two bytes long. The supplier ID (VID) is applied by the supplier to the USB for a forum, the vid of each supplier is unique, and the PID is determined by the supplier.

Vid and PID are usually stored in two modes: vid and PID of the master control manufacturer, which are stored in the bootcode of the master control, and vid and PID of the equipment manufacturer, the vid and PID are stored in a non-volatile storage device (EEPROM
OrFlash
)
When a USB device connects to the host, if the firmware contains the vid and PID of the device manufacturer, the vid and PID are reported to the host, the vid and PID of the master control manufacturer are ignored.
Therefore, in theory, the vid of a USB storage device should be the vid of the device manufacturer, rather than the vid of the master manufacturer. The two vids should be different (except for the devices produced by the master manufacturer ).
).

Because the duplicate vid and PID does not seriously affect the use of the product, many USB equipment manufacturers (most of the factory in shanzhai) do not apply for their own vid from the USB forum for convenience.

Is still using the vid of the master manufacturer or writing vid and PID to the product. At the same time,Regular manufacturers only need to apply for vid
,The PID is determined by the manufacturer.
So there are products of the same model, and different Controllers may be used (for commercial purposes, it is normal), while their PID is the same, based on the above reasons, the main control model of the USB device cannot be accurately identified through the vid and PID. This problem requires attention when using the USB device.

There are specialized software that can be detected, such as the tenglou Manor USB toolbox.

 

The PID and Vid files in the USB wireless network adapter (ralink 3070) driver are OS/Linux/usb_main_dev.c and rt3070sta. Mod. C.