Mi Band 1 Firmware Update¶

Getting the firmware¶

Since we may not distribute the firmware, you have to do a little work. You need to find and download a Mi Fit APK file. There is an APK Mirror Web site that might help you find Mi Fit. Extract the downloaded .apk file with "unzip", and you will find an assets/ directory containing *.fw files, among others.

Next, you need to find out, which of the *.fw files you need.

Some less interesting technical information is in Mi Band 1 Firmware Information.

Finding out the gadget model¶

Which Mi Band do you have? There are different models and each of them needs a different *.fw file.

1. Model 1 (coloured LEDs): Mili.fw

2. Model 1A (white LEDs): Mili_1a.fw

3. Model 1S (white LEDs + heart rate sensor): Mili_hr.fw

Installing the firmware on Mi Band 1, 1A, 1S models¶

Copy the desired Mi Band firmware as a *.fw file to your Android device and open it from any file manager on that device. The Gadgetbridge firmware update activity should then be started and guide you through the installation process.

Note 1: Both upgrade and downgrade of firmware versions is possible.

Mi Band 1S firmwares¶

Known firmware versions¶

As mentioned above, we are not allowed to distribute firmware files, these MD5 values may be used to check if the firmware file you obtained is valid/is not corrupted.

1. Model 1 (coloured LEDs): Mili.fw

   • 01.00.09.27 - de4e5f3bf1fb5b610b3261c7f3557ca7
   • 01.00.10.14 - 1c43d7f03c911f9ba8844ddd44bd8304
   • 01.00.11.06 - 2833690a70ec8c6699ccd3ac08b933cc
   • 01.00.12.00 - 3a941165b7b4e296ecd68cdfb0e01062
   • 01.00.15.00 - tested, works! SHA256: 7B29C5EA0325338AD703291A78D6107DEC458D1409CEF987F8E8A7FD570EB9C0

2. Model 1A (white LEDs): Mili_1a.fw

   • 05.15.11.20 - 356a8e1f006c541b76b306d4dbfbfaea
   • 05.15.12.10 - bbb904842a807acf1e2be5e2b41d888b

Additional information¶

Mi Band 1¶

• Data is aggregated per minute.
• The timestamp sent by the Mi Band may be any second of a given minute.
• When repeating a transfer (because the previous transmission was not ack'ed, for any reason) it may happen that the timestamp changes to a different second (within the same minute). This is currently an issue as multiple samples are being stored within Gadgetbridge database for the same minute.
• Multiple minutes are sent with a single transfer.
• The amount of minutes within each chunk depends on the Mi Band firmware, it's not predictable.
• It may span from some minutes to entire hours. The longer the period, the more likely the corruption of the data (as the only references are the beginning of each chunk).
• Each minute contains three values: number of steps, activity type, activity intensity.
• The known activity types are: "normal", "deep sleep", "shallow sleep", "device not worn".

Mi Band 1A and 1S¶

The firmware supports 3 different modes to measure the heart rate:

• a single measurement (as initiated from the debug screen).
• automatic measurement during sleep.
• continuous measurement, about one per second (as used in the live activity tracking screen).

Only the measurement during sleep is recorded on the band. The other measurement values are sent to the mobile only, so you have to be connected to get them. Maybe there are other ways to get the heart rate data recorded but we don't know them.