74HC4067/74HCT4067類比多工器可以切換16個類比腳位,只要接到MCU的一個類比腳位,

MCU就可以靠一個類比腳位,切換讀取74HC4067/74HCT4067類比多工器上的16個類比腳位,

在74HC4067/74HCT4067類比多工器上,s1,s2,s3,s4控制Y0-Y15的類比輸入腳位切換到到Z,

而Z接到Mega25602的類比腳位(如A0),因此只要控制s1,s2,s3,s4,Mega2560的A0就可以切換地讀取16個類比訊號源,

本範例的接腳為:

s0 --> digital 6;
s1 --> digital 5;
s2 --> digital 3;
s3 --> digital 2;
E --> digital 4; (設成Low output)

Z --> A0

Vcc --> 5V

GND --> GND

 

本範例參考: http://bildr.org/2011/02/cd74hc4067-arduino/

Arduino code:

//Mux control pins
int s0 = 6;
int s1 = 5;
int s2 = 3;
int s3 = 2;
int E = 4;

//Mux in "SIG" pin
int SIG_pin = 0;

void setup()
{
  pinMode(s0,OUTPUT);
  pinMode(s1,OUTPUT);
  pinMode(s2,OUTPUT);
  pinMode(s3,OUTPUT);
  pinMode(E,OUTPUT);
  digitalWrite(s0,LOW);
  digitalWrite(s1,LOW);
  digitalWrite(s2,LOW);
  digitalWrite(s3,LOW);
  digitalWrite(E,LOW);
 
  Serial.begin(9600);
 
}

void loop()
{
  //Loop through and read all 16 values
  //Reports back Value at channel 6 is: 346
  for(int i = 0; i < 16; i ++){
    Serial.print("Value at channel ");
    Serial.print(i);
    Serial.print("is : ");
    Serial.println(readMux(i));
    delay(1000);
  }
}

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;
}

接線圖 (有點混亂)

 

Serial Monitor:

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