The process of updating the operating system or restoring a Xiaomi smartphone often requires deeper intervention than a standard “over the air” update.Using the ADB (Android Debug Bridge) interface gives the user full control of the device, allowing you to install customized recaps, patch system partitions and even restore the phone after software failures.
Unlike simply copying files, working through the command line requires accuracy and understanding the command structure. A single character error can cause the device to refuse to boot. However, if you master the basics of interacting with Fastboot and ADB, you will have the opportunity to fully customize MiUI or HyperOS.
Before you take action, you need to understand the risks. Any interference in the system partition is always a balance between new features and stability, which is why we will discuss each step in detail below, from preparing drivers to the final installation of the firmware to minimize the likelihood of error.
Tools and drivers preparation
The foundation of successful firmware is a properly configured workplace. You'll need a Windows computer, because most of the tools for Xiaomi work best in this environment. USB-cable, preferably original, capable of transmitting data, and not only charging the battery.
A key element of preparation is to install the right drivers, without which the computer simply will not see the phone in bootloader mode, and users often find themselves in a situation where the device is defined as "Unknown device", which blocks further action.
- 📥 Download and install Universal ADB Driver and Qualcomm HS-USB QDLoader (for Snapdragon processors) or drivers MTK (MediaTek).
- 💻 Download the latest version of Platform Tools from the official Android Developers website to get the latest versions of adb.exe and fastboot.exe.
- 🔋 Make sure your smartphone battery is at least 60% battery power to avoid suddenly turning off at a critical moment.
Once the drivers are installed, it is recommended to restart the computer, which ensures that all system changes take effect and that there are no hardware conflicts.
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Use it. USB-ports soldered directly on the motherboard (back of the system unit) to avoid problems with power shortages or unstable connection through the front panel of the housing.
Activation of debugging and rights
In order for a computer to give commands to a smartphone, you need to activate a hidden developer menu. The standard MiUI hides these settings from random users. The first step is to enable debugging.
Go to your phone’s settings, select About Phone, and quickly click on MIUI Version (or OS Version). After a few clicks, a notification will appear that you have become a developer. Now a new section will appear in the “Additional” or “Extended Settings” menu.
☑️ Access setting
In the Developer menu, find the USB Debugging option and activate it. When you first connect the cable to your PC, you will see a request for debugging permission on your smartphone screen — be sure to click Allow and tick the Always Allow from this computer box.
⚠️ Note: Some global firmware versions may require a Mi Account account with confirmation via debugging when attempting to enable debugging SMS. Make sure you have funds on balance or use Wi-Fi.
Also worth paying attention to the status of the bootloader. To fully work with partitions through Fastboot, it must be unlocked. Check this by the fastboot oem device-info command, which will show the current state of Device unlocked.
Modes of operation: ADB and Fastboot
Understanding the difference between modes is critical. ADB works when Android is already booted or in Recovery mode, which allows you to transfer files, install applications and execute scripts.
Fastboot (or Bootloader) is run before the operating system boots, and this is where the low-level memory, boot, recovery, and system partitions are stored, and switch between modes is done either by software or by a combination of buttons.
| Parameter | ADB Mode | Fastboot Mode | Recovery Mode |
|---|---|---|---|
| Status of the OS | Busy or partially operational | Not loaded (low level) | Minimum environment |
| Substantive function | Debugging, file transfer | Partition firmware, unlocking | Reset, update installation |
| Appearance | Desktop or console | Screen with the Fastboot logo | Menu with items (Mi-Recovery) |
| Entry command | adb reboot bootloader | Volume + power buttons | adb reboot recovery |
To switch to firmware mode, the most common command is adb reboot bootloader. If the phone is turned off, press the volume button and connect the cable, the device will go to Fastboot mode, as reported by an image of a hare repairing an android.
What if your computer doesn’t see your phone in Fastboot?
Installation of custom Recovery (TWRP)
Mi-Recovery's regular repair service is limited in functionality and often does not allow the installation of modified firmware. TWRP (Team Win Recovery Project is a standard step for enthusiasts, and it gives you access to the file system, the ability to make full backups and install. ZIP-archive.
The installation process begins by finding the right.img image for your model, and using a file from another device is guaranteed to lead to a brick. Rename the downloaded file to twrp.img and place it in the folder with ADB tools.
Connect your phone in Fastboot mode and execute the command to check the connection:
fastboot devicesIf the serial number is displayed, you can start temporarily loading the Recovery. The fastboot boot twrp.img command will run the TWRP without writing to memory. This is a safe way to check the work! [sic] before the final installation.
- 🔍 Make sure the version TWRP Complies with the processor architecture and Android version.
- 🚫 Do not execute fastboot flash recovery command immediately, test the boot first.
- 📂 Copy the firmware file or Magisk patch to internal memory before restarting.
⚠️ Note: After the first loading in the installed TWRP The system may suggest "Keep Read Only." Swipe to Allow Modifications, or the reboot will overwrite the stock recavery. TWRP.
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Temporary boot (boot) is safer than direct firmware (flash), as it allows you to check the performance of the recovery without the risk of losing the regular recovery section.
Firmware process through Fastboot
The most reliable way to update or restore a system is to use the official firmware in Fastboot format (extension.tgz). The archive must be unpacked to get a set of scripts and image files. Inside the folder you will find files. flash_all.bat (for Windows or flash_all.sh (for Linux/Mac).
Script launch flash_all.bat It will automatically clean all the data and install a clean system, which is ideal for selling a phone or fixing deep software bugs. 5 before 15 minutes and does not require user intervention.
However, if you want to save data, you use the fastboot update command or specialized scripts without the wipe command, but remember that switching between regions (eg, from Global to China or vice versa) always requires complete cleaning.
fastboot flash boot boot.img
fastboot flash system system.img
fastboot flash vendor vendor.imgManually entering commands is only justified if the standard script produces an error at a certain stage, in which case you can flash only the damaged partition, saving the rest of the data intact.
Once all operations are complete, the phone will automatically go into reboot mode, and the first boot after the firmware can last up to 5-10 minutes — that's okay, the system optimizes applications.
Recovery from Errors (Unbrick)
Even experienced users sometimes face a situation where the phone stops responding to commands or goes into an endless restart (bootloop).If the device even enters Fastboot or Recovery mode, the situation can be fixed software.
In the case of hard breech, when the screen is black and the phone does not respond to buttons, EDL (Emergency Download Mode) mode may be required. To enter it, you often need to disassemble the phone and close the test points on the board, or use a special cable. In this mode, firmware is carried out through the MiFlash utility using an authorized service center account.
- 🔄 Try to execute the command fastboot reboot to get out of the got stuck state.
- 💾 Use the persist or modem backup if network signals are missing.
- 🛠 For difficult cases, use the Xiaomi utility ADB/Fastboot Tools with a graphical interface.
It is important to stay calm and follow the recovery steps consistently, and panic and chaotic button presses rarely help in such situations.