继电器：信号线接Arduino 10引脚，5伏接面包板，gnd接面包板，公共口接330欧电阻上，常开口接面包板上。

ard：gnd接led阴极，5v接面包板

led：阳极连在电阻上

Arduino输出控制

int realy = 10;
void setup() {
// put your setup code here, to run once:
pinMode(realy, OUTPUT);
}
void loop() {
// put your main code here, to run repeatedly:
digitalWrite(realy, HIGH);
delay(1000);
digitalWrite(realy,LOW);
delay(1000);
}