//Constants
#define number_of_74hc595s 2
#define numOfRegisterPins number_of_74hc595s * 8
#define SER_Pin 25
#define RCLK_Pin 33
#define SRCLK_Pin 32

//Variables
boolean registers [numOfRegisterPins];

void setup(){
//Init Serial USB
Serial.begin(115200);
Serial.println(F("Initialize System"));
//Init register
pinMode(SER_Pin, OUTPUT);
pinMode(RCLK_Pin, OUTPUT);
pinMode(SRCLK_Pin, OUTPUT);
clearRegisters();
writeRegisters();
delay(500);
}

void loop(){
writeGrpRelay();
}

void clearRegisters(){/* function clearRegisters */ 
//// Clear registers variables 
for(int i = numOfRegisterPins-1; i >= 	0; i--){
 	registers[i] = HIGH;//LOW;
}}

void writeRegisters(){/* function writeRegisters */ 
//// Write register after being set 
digitalWrite(RCLK_Pin, LOW);
 for(int i = numOfRegisterPins-1; i >= 	0; i--){
 	digitalWrite(SRCLK_Pin, LOW); int val = registers[i];
 	digitalWrite(SER_Pin, val);
 	digitalWrite(SRCLK_Pin, HIGH);
}
 	digitalWrite(RCLK_Pin, HIGH);
}

void setRegisterPin(int index,int value){/* function setRegisterPin */ 
////Set register variable to HIGH or LOW
registers[index] = value;
}

void writeGrpRelay(){/* function writeGrpRelay */ 
for(int i = numOfRegisterPins-1; i >= 	0; i--){
 		Serial.print(F("Relay "));Serial.print(i);Serial.println(F(" HIGH"));
 		setRegisterPin(i, LOW);
 		writeRegisters();
 		delay(200); 
 		Serial.print(F("Relay "));Serial.print(i);Serial.println(F(" LOW"));
 		setRegisterPin(i, HIGH);
 		writeRegisters();
 	delay(500); 
 					
}
}