CommentStreams:Dc0dcb68725c884437a9f9d05b1f4dc4

Hi，

①Please refer X728-Software#FAQ--Raspberry Pi Tutorial: How to Use a Buzzer

②AC FALL(AC Power Loss LED)----When AC power supply is not connected or power supply fails, the red indicator light is always on. If connected to AC power, the red indicator will not light up.