JY-MCU Bluetooth ワイヤレスシリアルポートモジュール（スレーブ）

After struggling with finicky Bluetooth modules for weeks, this slave unit paired instantly with my Arduino on the first try and has maintained a rock-solid connection across the room. The transmission speed is fast enough for real-time sensor data without noticeable lag.

Took me an afternoon to get the baud rate matched up with my project, but once it paired, the serial data flowed flawlessly between my microcontroller and laptop. The slave module stayed connected through a couple of walls, which is more than I expected from something this small.

Had my Arduino talking to my phone within ten minutes, and the slave mode paired instantly with a standard Bluetooth terminal app. The serial data transfer is rock solid for short distances, no dropped packets even with my hands in the way. Exactly what I needed for a quick wireless link in my proje