Problem with coding HC4051

Development Boards Arduino
1

Hi everyone, i hope i can get somehelp on how getting this to work.

I have multiple Sensors (32 of these) i want to read their values. I am using a master multiplexer HC4051 connected to 4 slave multiplexers, this is my wirings :

IBdBc.png438×538 23.5 KB
http://i.stack.imgur.com/IBdBc.png

And this is my code

// 74XX4051 ADDRESS PINS :
#define  M_S0 7
#define  M_S1 6
#define  M_S2 5

#define  S_S0 2
#define  S_S1 3
#define  S_S2 4

// 74XX4051 ANALOG PIN :
#define  Z 0


void setup(){

        // CONFIGURE ADDRESS PINS
        pinMode(M_S0, OUTPUT);
        pinMode(M_S1, OUTPUT);
        pinMode(M_S2, OUTPUT);

        pinMode(S_S0, OUTPUT);
        pinMode(S_S1, OUTPUT);
        pinMode(S_S2, OUTPUT);

        // CONFIGURE SERIAL
        Serial.begin(57600);
}

void loop () {

  int value;

  // LOOP THROUGH ALL THE ADDRESSES
    for ( byte count = 0; count < 32 ; count++ ) {

    digitalWrite(M_S0, HIGH); //TURN THE SENSOR ON FOR READING
    digitalWrite(M_S1, HIGH);
    digitalWrite(M_S2, HIGH);
    digitalWrite(S_S0, HIGH);
    digitalWrite(S_S1, HIGH);
    digitalWrite(S_S2, HIGH);

    // SET THE ADDRESS BITS
    digitalWrite(S_S0, bitRead(count, 0) );   // Slave A0
    digitalWrite(S_S1, bitRead(count, 1) );   // Slave A1
    digitalWrite(S_S2, bitRead(count, 2) );   // Slave A2

    digitalWrite(M_S0, bitRead(count, 3) );   // Master A0
    digitalWrite(M_S1, bitRead(count, 4) );   // Master A1
    digitalWrite(M_S2, bitRead(count, 5) );   // Master A2
    delay(50);

    // READ THE ANALOG VALUE
    value = analogRead(Z);

    digitalWrite(M_S0, LOW); //TURN THE SENSOR OFF WHEN READING IS DONE
    digitalWrite(M_S1, LOW);
    digitalWrite(M_S2, LOW);
    digitalWrite(S_S0, LOW);
    digitalWrite(S_S1, LOW);
    digitalWrite(S_S2, LOW);

    // SERIAL OUTPUT
    Serial.print(count, BIN);
    Serial.print('\t');
    Serial.println(value);
  }

  delay(3000);
}

1- All my sensors are in the air, so i should expect a “0” reading. but i’am getting really random reading from the serial monitor every cycle ! (4 of my sensors are not connected to the multiplexer, does make any interferance ?)

2- The part ```
digitalWrite(M_S0, HIGH); … digitalWrite(M_S0, LOW);