CD74HC4067 作用是选通一路对十六路模拟信号，就像一个单刀多掷开关，根据芯片上 S0-S3 四个不同管脚的组合，让SIG管脚和C0-C15导通（每次只能连接一个），它适用于数字和模拟信号，可以只用5针最多连接16传感器系统，也可以用它来管理多个设备。
//测量换算每个Pin的电压
int s0 = 34;
int s1 = 35;
int s2 = 32;
int s3 = 33;
int SIG_pin = 25;
void setup() {
// put your setup code here, to run once:
pinMode(s0, OUTPUT);
pinMode(s1, OUTPUT);
pinMode(s2, OUTPUT);
pinMode(s3, OUTPUT);
digitalWrite(s0, LOW);
digitalWrite(s1, LOW);
digitalWrite(s2, LOW);
digitalWrite(s3, LOW);
Serial.begin(115200);
}
void loop() {
// put your main code here, to run repeatedly:
int v;
for (int i = 0; i < 16; i ++)
{
Serial.print("Value at channel ");
Serial.print(i);
Serial.print(" is : ");
v = readMux(i);
Serial.println(v * 5.0 / 4096);
}
Serial.println(" ");
delay(3000);
}
int readMux(int channel)
{
int controlPin[] = {s0, s1, s2, s3};
int muxChannel[16][4] =
{
{0, 0, 0, 0}, //channel 0
{1, 0, 0, 0}, //channel 1
{0, 1, 0, 0}, //channel 2
{1, 1, 0, 0}, //channel 3
{0, 0, 1, 0}, //channel 4
{1, 0, 1, 0}, //channel 5
{0, 1, 1, 0}, //channel 6
{1, 1, 1, 0}, //channel 7
{0, 0, 0, 1}, //channel 8
{1, 0, 0, 1}, //channel 9
{0, 1, 0, 1}, //channel 10
{1, 1, 0, 1}, //channel 11
{0, 0, 1, 1}, //channel 12
{1, 0, 1, 1}, //channel 13
{0, 1, 1, 1}, //channel 14
{1, 1, 1, 1} //channel 15
};
//loop through the 4 sig
for (int i = 0; i < 4; i ++)
{
digitalWrite(controlPin[i], muxChannel[channel][i]);
}
//read the value at the SIG pin
int val = analogRead(SIG_pin);
//return the value
return val;
}
