Button I2C PCF8547 - Arquivo 016

Referência: 
http://www.dfrobot.com/

Montagem:

Firmware:
#include <Wire.h>

int NewX=0, OldX=0, y=0;
int ExitReadButton = 1,
    oldstate1 = 0,
    oldstate2 = 0,
    oldstate3 = 0,
    oldstate4 = 0,
    oldstate5 = 0,
    oldstate6 = 0,
    oldstate7 = 0,
    oldstate8 = 0;

const int Addr_Button = 0x38;

void setup(){
  Wire.begin();
  Serial.begin(9600);
}

void loop(){
  Wire.requestFrom(Addr_Button,1);    
  ReadButton();
  Serial.println(y);                                            
}

void ReadButton(){
  byte x;
  do{
   Wire.requestFrom (Addr_Button,1);
   if(Wire.available()) x = Wire.read();
   
   if (x == 254 && oldstate1 == 0) oldstate1 = 1;
   if (x == 255 && oldstate1 == 1){
     y = 0;
     oldstate1 = 0;
     ExitReadButton = 0;
   }
   
   if (x == 253 && oldstate2 == 0) oldstate2 = 1;
   if (x == 255 && oldstate2 == 1){
     y = 1;
     oldstate2 = 0;
     ExitReadButton = 0;
   }
   
   if (x == 251 && oldstate3 == 0) oldstate3 = 1; 
   if (x == 255 && oldstate3 == 1){
     y = 2;
     oldstate3 = 0;
     ExitReadButton = 0;
   }
   
   if (x == 247 && oldstate4 == 0) oldstate4 = 1; 
   if (x == 255 && oldstate4 == 1){
     y = 3;
     oldstate4 = 0;
     ExitReadButton = 0;
   }
   
   if (x == 239 && oldstate5 == 0) oldstate5 = 1; 
   if (x == 255 && oldstate5 == 1){
     y = 4;
     oldstate5 = 0;
     ExitReadButton = 0;
   }
   
   if (x == 223 && oldstate6 == 0) oldstate6 = 1; 
   if (x == 255 && oldstate6 == 1){
     y = 5;
     oldstate6 = 0;
     ExitReadButton = 0;
   }
   
   if (x == 191 && oldstate7 == 0) oldstate7 = 1; 
   if (x == 255 && oldstate7 == 1){
     y = 6;
     oldstate7 = 0;
     ExitReadButton = 0;
   }
   if (x == 127 && oldstate8 == 0) oldstate8 = 1; 
   if (x == 255 && oldstate8 == 1){
     y = 7;
     oldstate8 = 0;
     ExitReadButton = 0;
   }
  }while(ExitReadButton);
  delay(200);
  ExitReadButton = 1;
}

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