What is TWS audio synchronization ? Why need synchronization?

- Nov 03, 2019-

The full name of Bluetooth stereo (A2DP): Bluetooth high-quality audio transmission protocol, in order to ensure that the audio data received by the receiving end can have a higher degree of reduction, the transmitting end will compress and transmit the audio data first, and the receiving end receives the data. Decode and play again, the process usually takes tens or even hundreds of milliseconds

In the TWS application scenario, since TWS-Mater acts as both the audio receiving end and the transmitting end, and plays the same left and right channels of music with TWS-Slave, if the synchronization error between the two is large, it will easily cause people. Ear hearing discomfort

Feasycom's Bluetooth TWS can realize the audio synchronization error between the TWS-Master and TWS-Slave devices <1ms, which is far lower than the error range that can be resolved by the human ear.

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In addition to audio synchronization, event synchronization is also required between TWS-Master and TWS-Slave devices in many scenarios, such as volume, LED blinking status, shutdown, etc.

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TWS audio I/O mode

Feasycom TWS technology could support audio input mode

• Bluetooth: TWS-Master supports Bluetooth audio input and forwards to TWS-Slave

• LineIn: TWS-Master supports LineIn input and forwards to TWS-Slave

• Microphone: TWS-Master supports microphone input and forwards to TWS-Slave

Feasycom TWS technology could support audio output mode

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TWS pairing, connection

Feasycom TWS technology supports the Bluetooth 5.0 specification. After the device is powered on, it uses BLE to search and find the specified UUID device. It can improve the search speed and shorten the pairing time while ensuring the uniqueness of the connection.

TWS pairing and connection process:

• Bring device A to search mode

• Bring device B to broadcast mode

• Device A searches for peripheral devices through BLE, and initiates a connection if it finds that the UUID of device B meets the conditions.

• After the connection is successful, device A is TWS-Master, and device B is TWS-Slave. At this time, device A enters broadcast mode and waits for the audio transmitter (such as mobile phone) to connect.

• After the device A/B is successfully paired, it will record its own role type (such as A:TWS-Master, B:TWS-Slave) and the other party's Bluetooth address, and automatically connect back after the next time.

Feasycom TWS Audio Module;FSC-BT1006A