Extended Functions and Diagnostics

1. DFU mode for firmware update

DFU is the device firmware update mode.

To enter DFU mode:

1. Make sure the device is turned off.

2. Press and hold the button for more than 5 seconds.

3. Wait for the DFU indication.

In DFU mode, all three LEDs are steadily lit in their primary colors:

LED	Color
1	White
2	Blue
3	Red

To turn off the device from DFU mode, hold the button for more than 5 seconds.

2. Applying new firmware during startup

If the device detects new firmware during startup and applies it, all three LEDs are steadily lit in their secondary colors:

LED	Color
1	Cyan
2	Green
3	Yellow-green

danger

During this time, do not disconnect power and do not reset the device.

3. Forced hardware reset

If the device is on but does not respond to commands, press and hold the button for more than 12 seconds.

This performs a forced hardware reset. Use this function only if the device is frozen or cannot be turned off normally.

4. Ship mode

Ship mode is a deep power-saving mode for storage or transportation of the device.

To put the device into Ship mode:

1. Make sure the device is turned on.

2. Make 3 short button presses, each not more than 1 second.

3. The device shows preparation for Ship mode: all LEDs quickly blink 2 times in their secondary colors: cyan + green + yellow-green.

4. After this indication, hold the button for more than 3 seconds.

Before entering Ship mode, the device plays the complete signal.

To exit this mode, simply turn on the device by holding the button for more than 3 seconds.

5. Factory reset

Factory reset deletes user settings and returns the device to its initial state.

To perform factory reset:

1. Make sure the device is turned on.

2. Make 5 short button presses, each not more than 1 second.

3. The device shows preparation for reset: all LEDs quickly blink 4 times in their secondary colors: cyan + green + yellow-green.

4. After this indication, hold the button for more than 3 seconds.

5. The device performs reset and reboots.

Before reset, the device plays the complete signal.

6. Engineering mode

Engineering mode is intended for extended diagnostics of the device. Usually it is needed by a service specialist, but the user can use it to view battery status, Bluetooth connection quality and error code.

To enter engineering mode:

1. Make sure the device is turned on.

2. Make 4 short button presses, each not more than 1 second.

3. The device shows preparation for engineering mode: all LEDs quickly blink 4 times in their primary colors: white + blue + red.

4. After this indication, hold the button for more than 3 seconds.

5. The device plays the enter_special_mode melody.

In engineering mode, a short button press switches diagnostic screens in a loop:

Order	Diagnostic screen
1	Battery charge level
2	Bluetooth connection quality
3	Global device state error code

To exit engineering mode, hold the button for more than 3 seconds. Before exiting, the device plays the exit_special_mode melody.

7. Battery charge level indication in engineering mode

In this mode, only red LEDs are used.

Indication	Battery charge
1 red LED is lit	0-20%
2 red LEDs are lit	21-80%
3 red LEDs are lit	81-100%

8. Bluetooth connection quality indication

In this mode, only blue LEDs are used.

Indication	Connection quality
1 blue LED is lit	Low level
2 blue LEDs are lit	Medium level
3 blue LEDs are lit	High level
All blue LEDs blink quickly	There is currently no Bluetooth connection

9. Error code indication

The device can show a 32-bit global state code. This mode is intended for extended diagnostics.

Before code transmission starts, the 1st LED blinks quickly for about 2 seconds. Then the device cyclically shows the code by 2 bits per step:

LED	Purpose
1st LED	Reading synchronization. When it turns on in slow blinking mode, data can be read
2nd LED	Encodes one bit of the pair
3rd LED	Encodes the second bit of the pair

The code is transmitted in little-endian order, 2 bits per step, 32 bits in total. For a regular user, the simplified check is important:

What is visible	Meaning
Only the 1st LED blinks, the 2nd and 3rd do not light	Error code is zero, there are no critical errors
The 2nd or 3rd LED lights up	There is a non-zero state code; record the sequence or send the device for diagnostics

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