Bluetooth audio receiver XY-BT-MINI

Description

The board can convert almost any device, where is the 3.5 audio input to the bluetooth speaker.

To connect the power supply, the board has a microUSB connector and contacts for connecting a 3.7V battery..

For connecting an amplifier/headphones/radio/etc. have 3.5 audio jack.

чтение карты if ( ! mfrc522.PICC_ReadCardSerial()) return;