/*
addr 0 = A2 low , A1 low , A0 low  000
addr 1 = A2 low , A1 low , A0 high 001
addr 2 = A2 low , A1 high , A0 low  010
addr 3 = A2 low , A1 high , A0 high  011
addr 4 = A2 high , A1 low , A0 low  100
addr 5 = A2 high , A1 low , A0 high  101
addr 6 = A2 high , A1 high , A0 low  110
addr 7 = A2 high, A1 high, A0 high 111

Connect pin #12 of the expander to Analog 5 (i2c clock)
Connect pin #13 of the expander to Analog 4 (i2c data)
Connect pins #15, 16 and 17 of the expander to ground (address selection)
Connect pin #9 of the expander to 5V (power) // operation voltage is 1.8 to 5.5
Connect pin #10 of the expander to ground (common ground)
Connect pin #18 through a ~10kohm resistor to 5V (reset pin, active low)

Input #0 is on pin 21 so connect a button or switch from there to ground
*/
#include <Adafruit_MCP23017.h>
Adafruit_MCP23017 mcp1; // chip 1
Adafruit_MCP23017 mcp2; // chip 2
Adafruit_MCP23017 mcp3; // chip 3
Adafruit_MCP23017 mcp4; // chip 4
Adafruit_MCP23017 mcp5; // chip 5
Adafruit_MCP23017 mcp6; // chip 6
Adafruit_MCP23017 mcp7; // chip 7
Adafruit_MCP23017 mcp8; // chip 8

#define addr1 0
#define addr2 1
#define addr3 2
#define addr4 3
#define addr5 4
#define addr6 5
#define addr7 6
#define addr8 7

void setup()
  {
    Serial.begin(9600);
    mcp1.begin(addr1); mcp2.begin(addr2);
    mcp3.begin(addr3); mcp4.begin(addr4);
    mcp5.begin(addr5); mcp6.begin(addr6);
    mcp7.begin(addr7); mcp8.begin(addr8);

    mcp1.pinMode(0, OUTPUT); mcp1.pinMode(1, OUTPUT);
    mcp1.pinMode(2, OUTPUT); mcp1.pinMode(3, OUTPUT);
    mcp1.pinMode(4, OUTPUT); mcp1.pinMode(5, OUTPUT);
    mcp1.pinMode(6, OUTPUT); mcp1.pinMode(7, OUTPUT);
    mcp1.pinMode(8, OUTPUT); mcp1.pinMode(9, OUTPUT);
    mcp1.pinMode(10, OUTPUT); mcp1.pinMode(11, OUTPUT);
    mcp1.pinMode(12, OUTPUT); mcp1.pinMode(13, OUTPUT);
    mcp1.pinMode(14, OUTPUT); mcp1.pinMode(15, OUTPUT);

    mcp2.pinMode(0, OUTPUT); mcp2.pinMode(1, OUTPUT);
    mcp2.pinMode(2, OUTPUT); mcp2.pinMode(3, OUTPUT);
    mcp2.pinMode(4, OUTPUT); mcp2.pinMode(5, OUTPUT);
    mcp2.pinMode(6, OUTPUT); mcp2.pinMode(7, OUTPUT);
    mcp2.pinMode(8, OUTPUT); mcp2.pinMode(9, OUTPUT);
    mcp2.pinMode(10, OUTPUT); mcp2.pinMode(11, OUTPUT);
    mcp2.pinMode(12, OUTPUT); mcp2.pinMode(13, OUTPUT);
    mcp2.pinMode(14, OUTPUT); mcp2.pinMode(15, OUTPUT);

    mcp3.pinMode(0, OUTPUT); mcp3.pinMode(1, OUTPUT);
    mcp3.pinMode(2, OUTPUT); mcp3.pinMode(3, OUTPUT);
    mcp3.pinMode(4, OUTPUT); mcp3.pinMode(5, OUTPUT);
    mcp3.pinMode(6, OUTPUT); mcp3.pinMode(7, OUTPUT);
    mcp3.pinMode(8, OUTPUT); mcp3.pinMode(9, OUTPUT);
    mcp3.pinMode(10, OUTPUT); mcp3.pinMode(11, OUTPUT);
    mcp3.pinMode(12, OUTPUT); mcp3.pinMode(13, OUTPUT);
    mcp3.pinMode(14, OUTPUT); mcp3.pinMode(15, OUTPUT);

    mcp4.pinMode(0, OUTPUT); mcp4.pinMode(1, OUTPUT);
    mcp4.pinMode(2, OUTPUT); mcp4.pinMode(3, OUTPUT);
    mcp4.pinMode(4, OUTPUT); mcp4.pinMode(5, OUTPUT);
    mcp4.pinMode(6, OUTPUT); mcp4.pinMode(7, OUTPUT);
    mcp4.pinMode(8, OUTPUT); mcp4.pinMode(9, OUTPUT);
    mcp4.pinMode(10, OUTPUT); mcp4.pinMode(11, OUTPUT);
    mcp4.pinMode(12, OUTPUT); mcp4.pinMode(13, OUTPUT);
    mcp4.pinMode(14, OUTPUT); mcp4.pinMode(15, OUTPUT);

    mcp5.pinMode(0, OUTPUT); mcp5.pinMode(1, OUTPUT);
    mcp5.pinMode(2, OUTPUT); mcp5.pinMode(3, OUTPUT);
    mcp5.pinMode(4, OUTPUT); mcp5.pinMode(5, OUTPUT);
    mcp5.pinMode(6, OUTPUT); mcp5.pinMode(7, OUTPUT);
    mcp5.pinMode(8, OUTPUT); mcp5.pinMode(9, OUTPUT);
    mcp5.pinMode(10, OUTPUT); mcp5.pinMode(11, OUTPUT);
    mcp5.pinMode(12, OUTPUT); mcp5.pinMode(13, OUTPUT);
    mcp5.pinMode(14, OUTPUT); mcp5.pinMode(15, OUTPUT);

    mcp6.pinMode(0, OUTPUT); mcp6.pinMode(1, OUTPUT);
    mcp6.pinMode(2, OUTPUT); mcp6.pinMode(3, OUTPUT);
    mcp6.pinMode(4, OUTPUT); mcp6.pinMode(5, OUTPUT);
    mcp6.pinMode(6, OUTPUT); mcp6.pinMode(7, OUTPUT);
    mcp6.pinMode(8, OUTPUT); mcp6.pinMode(9, OUTPUT);
    mcp6.pinMode(10, OUTPUT); mcp6.pinMode(11, OUTPUT);
    mcp6.pinMode(12, OUTPUT); mcp6.pinMode(13, OUTPUT);
    mcp6.pinMode(14, OUTPUT); mcp6.pinMode(15, OUTPUT);

    mcp7.pinMode(0, OUTPUT); mcp7.pinMode(1, OUTPUT);
    mcp7.pinMode(2, OUTPUT); mcp7.pinMode(3, OUTPUT);
    mcp7.pinMode(4, OUTPUT); mcp7.pinMode(5, OUTPUT);
    mcp7.pinMode(6, OUTPUT); mcp7.pinMode(7, OUTPUT);
    mcp7.pinMode(8, OUTPUT); mcp7.pinMode(9, OUTPUT);
    mcp7.pinMode(10, OUTPUT); mcp7.pinMode(11, OUTPUT);
    mcp7.pinMode(12, OUTPUT); mcp7.pinMode(13, OUTPUT);
    mcp7.pinMode(14, OUTPUT); mcp7.pinMode(15, OUTPUT);

    mcp8.pinMode(0, OUTPUT); mcp8.pinMode(1, OUTPUT);
    mcp8.pinMode(2, OUTPUT); mcp8.pinMode(3, OUTPUT);
    mcp8.pinMode(4, OUTPUT); mcp8.pinMode(5, OUTPUT);
    mcp8.pinMode(6, OUTPUT); mcp8.pinMode(7, OUTPUT);
    mcp8.pinMode(8, OUTPUT); mcp8.pinMode(9, OUTPUT);
    mcp8.pinMode(10, OUTPUT); mcp8.pinMode(11, OUTPUT);
    mcp8.pinMode(12, OUTPUT); mcp8.pinMode(13, OUTPUT);
    mcp8.pinMode(14, OUTPUT); mcp8.pinMode(15, OUTPUT);
    Serial.println("SISTEM ISHE BASHLAYIR");
    delay(500);
    Serial.println("ZEHMET OLMAZSA BiR REQEM DAXiL EDIN");
  }

  void loop()
  {
if (Serial.available() > 0) {
    int gelen = Serial.read();
    switch (gelen) {
      case '1':
  mcp1.digitalWrite(0, HIGH);
  Serial.println("a1 OK");
  delay(100);
  mcp1.digitalWrite(0, LOW);
        break;
      case '2':
  mcp2.digitalWrite(0, HIGH);
  Serial.println("a2 OK");
  delay(100);
  mcp2.digitalWrite(0, LOW);
        break;
      case '3':
  mcp6.digitalWrite(0, HIGH);
  Serial.println("a3 OK");
  delay(100);
  mcp6.digitalWrite(0, LOW);
        break;
      case '10':
  mcp7.digitalWrite(0, HIGH);
  Serial.println("a4 OK");
  delay(100);
  mcp7.digitalWrite(0, LOW);
        break;
      case '11':
  mcp8.digitalWrite(0, HIGH);
  Serial.println("a5 OK");
  delay(100);
  mcp8.digitalWrite(0, LOW);
        break;
      default:
      break;
      }
 }
  }