Modifying vendor and device identifiers often becomes necessary when standard drivers stop working or emulation of different hardware is required. In the world of networking technologies VID (Vendor ID) and PID (Product ID) act as a digital passport by which the operating system recognizes the connected device. Changing these parameters allows you to bypass software locks, restore a non-functional adapter after an unsuccessful firmware update, or activate hidden chipset features.
The modification process isn't a trivial task for a beginner, as it requires an understanding of USB device architecture and firmware operation. Errors during the flashing process can cause the computer to stop recognizing the adapter altogether, rendering it a useless piece of plastic. However, with the right approach and specialized software, it's possible. Realtek or MediaTek it is possible to successfully reanimate the equipment.
In this article, we'll take a detailed look at methods for changing identifiers, the necessary tools, and software solutions for various chipsets. You'll learn how to use traffic sniffers to determine the required values and the risks associated with tampering with the service memory area. It is critical to understand that changing the VID PID does not change the physical characteristics of the antenna or the transmitter power, but only adjusts the software identification.
⚠️ Warning: Any actions involving changing identifiers are performed at your own risk. Incorrectly writing data to the EEPROM may permanently damage the device and leave it unrecoverable using software.
Theoretical Foundations: What are VID and PID?
Every USB device connected to a computer is required to communicate information about itself to the host. This information is stored in a special memory area and contains two hexadecimal codes. Vendor ID — is a unique number assigned to the chip manufacturer by the USB-IF consortium. This is how the system understands that it has a product from Realtek, Ralink or Atheros.
The second parameter, Product ID, assigned by the manufacturer for a specific device model. The combination of these two numbers allows the operating system to select the appropriate driver from the database. If you change these values, you effectively trick the system into thinking a completely different device is connected to the port.
Why is this necessary in the context of WiFi adapters? Manufacturers often release the same hardware platform with different PIDs for different regions or carriers. By changing the PID, you can unlock features that were restricted by software. Furthermore, this is the only way to restore the adapter if the factory identifiers were damaged during the process of flashing alternative firmware.
Technical details of the USB descriptor structure
The device descriptor contains the bcdUSB, idVendor, idProduct, and bcdDevice fields. The idVendor field is 2 bytes and is always the same for all products from the same vendor. The idProduct field also occupies 2 bytes and is unique for each model. Changing these fields in the EEPROM changes the device's response to the GET_DESCRIPTOR request from the host.
Necessary tools and preparation
Before beginning the practical part, you need to prepare your workstation and software. You'll need a computer running Windows, as most EEPROM utilities are written specifically for this platform. You'll also need the original firmware file or a memory dump containing the correct factory settings.
Specialized utilities are used to interact with the adapter's firmware. For chips Realtek this is often RTWlanUI.exe or RTWlanU.exe. For MediaTek (Ralink) — RT2870UI.exeIf standard utilities are not suitable, you have to resort to low-level programmers, such as Ivport or ChipGenius for diagnostics.
- 🛠️ Specialized software for writing EEPROM (depending on the chipset).
- 💾 Drivers for a specific WiFi module in compatibility mode.
- 📑 Hex editor for analyzing and editing binary firmware files.
- 🔌 Stable USB 2.0 port without hubs or extension cables.
It's important to ensure a stable power supply. A power surge or accidental device shutdown during recording can corrupt the service area. It's recommended to use ports on the rear panel of the system unit, connected directly to the motherboard.
Change procedure for Realtek adapters
Chipsets from the company Realtek are among the most common in the budget and mid-range segments. The process of changing identifiers here often comes down to using official configuration utilities, if the manufacturer allows this option, or third-party programmers. The standard route is usually through the menu. Tools in the configuration utility.
If the standard utility doesn't provide access to the VID/PID fields, you'll have to use the "spoofing" method. First, the current configuration is read, then the bytes responsible for the identifiers are found in a hex editor. These bytes are usually located at the beginning of the dump file. After editing, the file is loaded back into the device.
The algorithm of actions is as follows:
- Launch the adapter management utility.
- Go to the section
Advanced SettingsorEEPROM Tool. - Find the fields Vendor ID And Product ID.
- Enter new values in hexadecimal format.
- Click the button
WriteorProgram.
⚠️ Note: Utility interfaces may differ depending on the driver version and specific chip model (e.g., RTL8812AU vs. RTL8188EU). Always compare screenshots with your software version.
After recording, you must completely power off the adapter. Simply reconnecting the USB cable may not be sufficient, as the controller may cache old values. Remove the device from the port, wait 5-10 seconds, and reinsert it. Check for changes in Device Manager.
☑️ Check the result
Works with MediaTek and Ralink chipsets
Devices based on MediaTek (previously Ralink) have their own characteristics. Often, working with them requires switching the adapter to a special testing mode. This may require holding down a button on the housing while connecting or using a key combination. Without switching to this mode, writing to the EEPROM will be blocked.
The software for these chips is often called RT28xx WPS Utility or similar names. Unlike Realtek, here changing the VID/PID may require editing the configuration file RT2860.ini or similar, if the utility supports reading settings from it at startup.
There's also a method for reflashing firmware with already modified headers. You take the existing firmware binary, open it in a hex editor, find the offset of the identifier bytes (usually the first 256 bytes), and change them. Then, you flash this modified file using the standard update utility.
It is worth noting that some modern adapters MediaTek are write-protected. In this case, modification is only possible with physical access to the EEPROM contacts and the use of a programmer such as CH341AThis is already a level of hardware repair, requiring soldering skills.
Using sniffers and traffic analysis
In complex cases where standard methods fail, USB traffic sniffers can help. These tools allow you to see exactly what data a device transmits when connected. By analyzing packets, you can determine exactly where in memory the required bytes are stored and what they should look like.
A popular tool is USBPcap in conjunction with WiresharkWith their help, you can intercept the moment the system polls the device. You will see a request GET_DESCRIPTOR and the device's response, containing the current VID and PID. Comparing this response with the expected one helps identify discrepancies.
The table below shows an example structure of a device descriptor response:
| Parameter | Description | Example of meaning | Length |
|---|---|---|---|
| bLength | Descriptor length | 0x12 | 1 byte |
| bDescriptorType | Descriptor type (DEVICE) | 0x01 | 1 byte |
| idVendor | Manufacturer's ID | 0x0BDA (Realtek) | 2 bytes |
| idProduct | Product ID | 0x8179 | 2 bytes |
| bcdDevice | Device version | 0x0200 | 2 bytes |
Using this data, you can create a fake response or modify the driver to accept a device with modified parameters. This is a more complex approach, requiring in-depth knowledge of the USB protocol, but it gives you maximum control.
Traffic analysis also helps determine whether the driver itself is blocking the write. If you see a packet with a transmission error after the write command, it means the protection was triggered or the command was formed incorrectly.
Recovery after unsuccessful modification
If the adapter disappears from the system after changing its ID or is detected as an "Unknown Device," don't panic. In most cases, the controller remains functional, but its firmware is corrupted. The first step is to try to locate the device by its chip's Vendor ID, even if the Product ID has changed to an incorrect one.
Use the utility ChipGenius or USBDeviewIf the program detects the device and displays its Vendor ID (e.g., 0x0BDA for Realtek), the USB controller is functioning. In this case, you can try flashing the original firmware, ignoring the PID check if the utility allows it.
If software methods fail, the only option is to disassemble the device. Find the EEPROM chip on the adapter board (it's a small 8-pin chip next to the main chip). Shorting certain contacts (date and click) or using a programmer will allow you to read and write a clean memory dump directly, bypassing the USB controller.
How to find contacts for shorting (Data+ and GND)?
Entering recovery mode often requires shorting the Data+ (D+) pin to ground (GND) when connecting the USB. On the board, look for traces running from the USB connector to the chip. D+ typically has a resistance of about 22-47 ohms relative to the controller. Be careful not to short the 5V supply to ground.
Is it possible to repair an adapter without soldering?
Sometimes a hot-plugging method helps. Hold down the button (if applicable), connect the USB, and release the button after 2-3 seconds. Or try connecting the device via a non-powered USB hub so that there's not enough current for normal booting, but enough to enter bootloader mode.
What to do if the VID has changed to 0000?
A value of 0000 indicates that the identification section is empty or damaged. In this case, automatic driver installation is impossible. You will have to manually specify the driver's INF file, matching it with the current (even zero) ID, for the system to allow the flashing utility to run.
Frequently Asked Questions (FAQ)
Will the MAC address change if I change the VID PID?
No, the MAC address is stored in a different EEPROM memory cell. However, some utilities may change all parameters at once if you download a full dump from another device. Always check the MAC address after the procedure.
Will this affect WiFi speed?
Changing the IDs themselves doesn't affect the physical data transfer rate. However, if you've upgraded your device to a model that supports a wider channel or a different standard (for example, from 20 MHz to 40 MHz), and the driver allows it, the speed may increase.
Is it possible to bypass MAC address blocking by a provider?
Theoretically, yes, if the provider blocks by MAC address. However, more often, blocking occurs based on the MAC address and hardware type. Changing the VID/PID can help disguise the device, but it's not a guaranteed way to bypass restrictions.
Where can I get the correct VID and PID for my model?
The best source is the manufacturer's official website or forums where EEPROM dumps for your specific board revision are posted. You can also view the values on a working device of the same model using Device Manager.