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jfpoilpret
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How to code for cascading multiplexers?

I hope I can get some help on how to get this to work.

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

I tested it using one single multiplexer and it works as intended, but when adding the slave I cannot getting it to work, I am not sure how to code for it.

When using this code:

// 74XX4051 ADDRESS PINS :
#define  M_S0 2
#define  M_S1 3
#define  M_S2 4

#define  S_S0 7
#define  S_S1 6
#define  S_S2 5

// 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 OF THE MASTER 
    for ( byte count = 0; count < 4 ; count++ ) {
         // SET THE ADDRESS
         digitalWrite(M_S0, bitRead(count, 0) );   
         digitalWrite(M_S1, bitRead(count, 1) );
         digitalWrite(M_S2, bitRead(count, 2) );
                
         // LOOP THROUGH ALL THE ADDRESSES OF THE SLAVES
         for ( byte count_1 = 0; count_1 < 32 ; count_1++ ) {
             digitalWrite(S_S0, bitRead(count_1, 0) );
             digitalWrite(S_S1, bitRead(count_1, 1) );
             digitalWrite(S_S2, bitRead(count_1, 2) );

             // READ THE ANALOG VALUE
             value = (bitRead(count_1, 2), bitRead(count_1, 1), bitRead(count_1, 0));
         }

         // READ THE ANALOG FOR THE MASTER ADRESSE
         value = analogRead(Z);

         // SERIAL OUTPUT
         // print : ### value
         Serial.print(bitRead(count, 2));
         Serial.print(bitRead(count, 1));
         Serial.print(bitRead(count, 0));
         Serial.print(' ');
         Serial.println(value);

         delay(100);
     }
}

I am only getting random readings really (the reading LED for the moisture sensor does not switch on when the reading is done).

What I am doing wrong? Any help is appreciated.

mounim
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