How to use it NFC Xiaomi 9T: full instruction with pictures and life hacks

Xiaomi 9T

Redmi K20 Pro

NFC

all-in-all NFC

Xiaomi 9T

MIUI 12/13/14

Let’s just note: despite the fact that the smartphone Released in 2019, his NFC-module NXP PN80T) It's still one of the most versatile of the budget flagships. HCE (Host Card Emulation for Bank Cards, NFC-F (FeliCa for Japanese transponders and even NFC-V You can do this for some smart locks, but to make it work, you have to set up the system right, and that's where the first setbacks start.

If you’ve never used contactless technology, don’t worry: we’ll start with the basics of how to turn it on. NFC, Link the card and pay for the purchase. Advanced scenarios: emulating passes, automating with tags, and circumventing regional restrictions (for example, for Google Pay in countries where it is not officially supported) will be useful for experienced users).

1. How to turn on NFC Xiaomi 9T: step-by-step

The first thing you need to do is activate the module itself. 9T It's turned off by default to save battery power. NFC literally in two tapas, but there are nuances depending on the version MIUI.

Open the Settings. → Connections and sharing → NFC. If there is no such item, then your firmware uses the old menu structure - try the Settings path. → Additionally. → Wireless networks → NFC. Insert the slider in the "On" position.».

Slideer NFC on (should burn green)

Android Beam (Data Transfer) Mode Activated

There's a badge in the status line. NFC (If it is not, restart the smartphone)

Download the test application (for example, NFC Tools for inspection -->

Important: Some custom firmware (e.g. Pixel Experience or LineageOS) have a way to set up NFC If you can't find this section, check if the module is disabled at the kernel level, which happens after an incorrect update.

After activating the module, we recommend you to immediately update Google Play and Google Pay services (if you plan to use payments). → Profile → Device control → Updates and install all available updates.

⚠️ Attention: On Xiaomi 9T firmware MIUI 12.5 may not work emulation of cards in the background. NFC It shuts down after 5 minutes of inactivity. Solution: Update the firmware or use the app. NFC ReTag for Forced Connection Retention.

2.Configure contactless payments: Google Pay, SberPay, Mir Pay

Main application NFC — Paying for purchases with a smartphone. 9T All popular payment systems are supported, but there are regional restrictions, so let's figure out how to tie a card in each case.

For Google Pay (now Google Wallet), the algorithm is as follows:

1. Install the Google Wallet app from the Play Store.
2. Open it and click “Add Card” → “Credit or Debit Card”.
3. Scan the map with the camera or enter the data manually.
4. Confirm the binding via SMS or banking application.

SberPay and Mir Pay are configured via the same app, and the main difference is that they require support. HCE (Host Card Emulation, which is available on Xiaomi 9T However, some banks (such as Tinkoff or Alfa Bank) can block card binding to smartphones with the bootloader unlocked. If you encounter a device not supported error, try it:

Compare the payment systems in the table:

⚠️ Note: If payments fail after the card is tied, check if the energy saving mode for the payment system application is turned on. → Annexes → Application management → Google Wallet → Battery and select "No restrictions».

3. Data transmission by NFC: Android Beam and Alternatives

Besides payments, NFC Xiaomi 9T It allows you to quickly share files, contacts and links with other devices, using Android Beam technology, but Google has officially stopped supporting it since 2020.

To transmit the file:

1. Turn on NFC on both devices.
2. Open the file (photo, contact, web page) in the appropriate application.
3. Combine the back of smartphones (antenna) NFC Located at the top of Xiaomi 9T, near-camera).
4. Wait for the sound signal and vibration – the transmission will begin automatically.

If Android Beam doesn’t work, use third-party apps:

• 📱 NFC Tools – allows you to create your own tags and transfer text, links, Wi-Fi passwords.
• 📎 Send Anywhere – an alternative to transfer files over the Internet NFC (requires installation on both devices).
• 🔗 Trigger – Automation of actions on the NFC (For example, turning on Bluetooth when touching a tag).

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If file transfers are constantly disrupted, try turning off the system's power saving mode. → Battery → Performance mode and select “No Limits” for transfer time.

Transmission speed NFC It is low (up to 424 kbps), so it is better to use Wi-Fi Direct or Bluetooth 5.0 for large files. NFC wins in convenience – no need to search for a device in the list or enter passwords.

4. Work with NFC-Labels: Automation and Smart Home

One of the most interesting functions NFC — Tags are small stickers or key fobs that can be programmed to perform certain actions when touched by a smartphone. 9T It works through applications like this. NFC Tools or Trigger.

Examples of use of tags:

• 🏠 Smart home: Touching a mark at the door turns on Wi-Fi, launches a smart lock app and sends a homecoming notification.
• 🚗 Car: The tag in the car activates Bluetooth, triggers the navigator and turns on the economical battery mode.
• 🛏️ Bedroom: Touching the label on the nightstand puts the phone in Do Not Disturb mode and reduces the brightness of the screen.
• 💼 Office: A label on the desktop opens the corporate VPN, Slack launches and disables notifications from social networks.

To program the tag:

1. Buy the empty ones. NFC-stickers (e.g., stickers, NTAG213 or NTAG215).
2. Install the app NFC Tools from Play Store.
3. Select "Write down» → «Add a record» → specify the action (URL, text, command, etc.).
4. Apply a tag to the back of the smartphone and wait for the recording confirmation.

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For complex scenarios (e.g., enabling multiple smart home devices), use Tasker in conjunction with the NFC Tools. This will allow you to start chains of action with one touch.

If the tag doesn't work:

• Check that it is compatible with Xiaomi. 9T (should be maintained NFC Forum Type 2).
• Make sure there is enough memory on the tag (for example, for URL enough NTAG213, And you need complex teams. NTAG216).
• Rewrite the tag – sometimes the data is damaged when used for the first time.

5. Emulation of access cards, passes and transport tickets

Xiaomi 9T can emulate access cards (for example, for an office or entrance), transport tickets (in cities with support) NFC-There are technical and legal nuances to this, but there are student tickets.

To emulate the passes, you will need:

1. Download the appendix NFC Card Emulator or Mifare Classic Tool.
2. Read the original map (if any) - to do this, attach it to your smartphone and save the dump.
3. Write the dump to a virtual card in your phone or to a reprogrammable tag (e.g, NTAG216).

Important: Not all access cards can be copied.

• ✅ Mifare Classic 1K — copy without any problems.
• ⚠️ Mifare Ultralight – Copyable, but may not work with some readers.
• ❌ Mifare DESFire – not copied due to encryption.
• ❌ HID iClass – requires specialized equipment.

For transport cards (for example, Troika in Moscow or Posrodnik in Minsk), the situation is more complicated:

• Officially, their emulation on smartphones is not supported - a physical card is required.
• Unofficial methods (via the Mifare Classic Tool) only work with outdated versions of cards and can result in a lockdown.
• In some cities (for example, Kazan) to test the fare through Mir Pay is a legal alternative.

6.Problems with NFC Xiaomi 9T and their decisions

Even on a proper device. NFC It can malfunction. We'll look at the typical problems and how to fix them.

Problem 1: NFC It does not turn on or immediately switch off.

• 🔋 Check the battery power – at a level below 5%, the module automatically deactivates.
• 🔄 Restart your smartphone in Safe Mode (hold the power button) → «Restart in Safe Mode. “If NFC earned - the fault of the third-party application.
• 🛠️ Update the firmware to the latest version MIUI Or roll back to a stable build if you use the beta version.

Problem 2: Payments are not accepted (card is not supported).

• 💳 Make sure the bank supports contactless payments through HCE.
• 🔒 Check if the Root access or unlocked bootloader is blocked (some banks block such devices).
• 📱 Reset your Google Play Services settings in Settings → Annexes → Application management → Google Play Services → Warehouse → Clear the data.

Problem 3: The smartphone can't see NFC-marker.

• 📍 Check the location of the antenna – on Xiaomi 9T It's on the top of the back, next to the camera.
• 🛡️ Remove the case – some models with metal inserts screen the signal.
• 🔄 Rewrite the tag with another device (e.g. iPhone with iOS 13)+).

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If NFC It stopped working after the smartphone fell, most likely the antenna or the chip itself is damaged, in which case only replacing the module in the service center (cost is from 1500 to 3000) will help. ₽).

To diagnose hardware problems, use the engineering menu:

1. Please dial the phone application ##4636##.
2. Select "Equipment Testing» → «NFC».
3. If the Failed status is a malfunction at the iron level.

7. Advanced scenarios: NFC for developers and enthusiasts

If you are not limited to basic features, Xiaomi 9T It offers opportunities for experimentation. NFC for:

• 🤖 Automation of tasks through Tasker + NFC Tools (for example, running a script when touching a tag).
• 🔐 Two-factor authentication – some services (e.g. YubiKey) support NFC-keynote.
• 🎮 Game controllers – you can program the tag to emulate button presses (useful for automatic actions in games).
• 📡 Transfer Wi-Fi passwords to guests without disclosing the password itself (through a tag with an encrypted link).

To work with RAW-data NFC (For example, for research protocols, an application will be suitable. NFC Gateway, it allows:

• Read and write UID marker.
• Emulate Mifare Classic and Ultralight cards.
• Analyze APDU-commands (protocol of data exchange with the NFC-device).

<uses-permission android:name="android.permission.NFC" />


<uses-feature android:name="android.hardware.nfc" android:required="true" />

For enthusiasts who want to dive deeper, the following resources are useful:

• 📖 Documentation. NXP PN80T (chip used in Xiaomi 9T).
• 🛠️ The libnfc project for working with NFC Linux-level.
• 🤝 Community XDA Developers – there are guides on modifications NFC-custom-stack.

FAQ: Frequent questions on NFC Xiaomi 9T