// How many of the shift registers
#define NUM_SHIFT_REGS_74HC165 1
#define NUM_SHIFT_REGS_74HC595 1

const uint8_t num74hc165Pins = NUM_SHIFT_REGS_74HC165 * 8;
const uint8_t num74hc595Pins = NUM_SHIFT_REGS_74HC165 * 8;

// Define Connections to 74HC165
int dataIn = 2;               // Q7 pin 09
int clockIn_clockOut = 3;     // CP pin 02
int load =4;                  // PL pin 01
int clockEnable_lachSTCP = 5; // CE pin 15

// Define Connections to 74HC595
//int latchPin = 7;       // ST_CP pin 12
int dataOut = 8;          // DS    pin 14
//int clkPin = 9;         // SH_CP pin 11
int outputEnablePin = 10; // OE  pin 13

// Read Button
int readButton = 11;
bool statusButton = 0;
bool startReadWrite = 0;
bool debug = 0;

byte data74hc165 = 0;
byte last74hc165 = 0;
byte data74hc595 = 0;
//byte last74hc595 = 0;

boolean registers[num74hc595Pins];
boolean enable = 0;



/////////////////////////////////////
void setup() { 
  Serial.begin(15200); 
  // Setup 74HC165 connections
  pinMode(load, OUTPUT);
  pinMode(clockEnable_lachSTCP, OUTPUT);
  pinMode(clockIn_clockOut, OUTPUT);
  pinMode(dataIn, INPUT);
  // Setup 74HC595 connections
  //pinMode(latchPin, OUTPUT);
  pinMode(dataOut, OUTPUT);  
  //pinMode(clkPin, OUTPUT);
  pinMode(outputEnablePin, OUTPUT);
  digitalWrite(outputEnablePin, LOW);
}

void writeRegisters(){

  digitalWrite(clockEnable_lachSTCP, LOW);

  for(int i = num74hc595Pins - 1; i >=  0; i--){
    digitalWrite(clockIn_clockOut, LOW);

    int val = registers[i];

    digitalWrite(dataOut, val);
    digitalWrite(clockIn_clockOut, HIGH);

  }
  digitalWrite(clockEnable_lachSTCP, HIGH);

}

//set an individual pin HIGH or LOW
void setRegisterPin(int index, int value){
  registers[index] = value;
}

 /////////////////////////////////////
void loop() {

  setRegisterPin(0, HIGH);
  setRegisterPin(3, HIGH);
  setRegisterPin(4, LOW);
  setRegisterPin(5, HIGH);
  setRegisterPin(6, HIGH);


  writeRegisters();  //MUST BE CALLED TO DISPLAY CHANGES
  //Only call once after the values are set how you need.


  if (statusButton != digitalRead(readButton) ){
    startReadWrite = 1;
  }

  if (startReadWrite == 1) {
    enable != enable;
    digitalWrite(outputEnablePin, enable);
    startReadWrite =0;
  }

  //delay(500);
}
  
/*
// Gravacao e Leitura Placa Rele DT_CH16
  
  // Start
  digitalWrite(clockEnable_lachSTCP, 0);              // (Pin 15 Esp32) Conectado ao CI C04F (inversor sinal) e porta 01 74hc165 (em Low le os dados(paralela) para buffler) ****
                                                   // (Pin 15 Esp32) To Low (Storage register 595 desativa e CLOCK INHIBIT 165 desativa)

  // relay out to '595                                                   
  for ( int i = num74hc595Pins ; i > 0 ; i-- ) {
    digitalWrite(dataOut, data74hc595 & 1);  // (Pin 13 Esp32) "outputs & 1" Operador AND Bitwise(&) se ambas entradas são 1, a saída resultante é 1, do contrário o resultado é 0.  **** "outputs" variavel tipo bit saida
    data74hc595 >>= 1;                                 //                "outputs >>= 1" Operador de deslocamento à direita(>>) o número '1' depois dele especifica o quanto ele deve ser deslocado.
    // generate CLK pulse
    digitalWrite(clockIn_clockOut, 1);            // (Pin 14 Esp32) Clock de subida High para ler proximo bit.
    digitalWrite(clockIn_clockOut, 0);            // (Pin 14 Esp32) Clock Low estaciona bit.
  }
  // ending
  digitalWrite(clockEnable_lachSTCP, 1);              // (Pin 15 Esp32) to High (Storage register ativa os dados da saida paralela do 595 e CLOCK INHIBIT 165 ativa)


  // input from '165
  for ( int i = num74hc165Pins ; i > 0 ; i-- ) {
    data74hc165 |= digitalRead(dataIn) ? last74hc165 : 0;  // (Pin 14 Esp32) **** "in_bit" variavel tipo bit entrada
    last74hc165 <<= 1;                                  // "outputs <<= 1" Operador de deslocamento à esquerda(<<) o número '1' depois dele especifica o quanto ele deve ser deslocado.
    // generate CLK pulse
    digitalWrite(clockIn_clockOut, 1);            // (Pin 14 Esp32) Clock de subida High para ler proximo bit.
    digitalWrite(clockIn_clockOut, 0);            // (Pin 14 Esp32) Clock Low estaciona bit.
  }  

  if (statusButton != digitalRead(readButton) ){
    startReadWrite = 1;
  }

  if (startReadWrite == 1) {
  // Get data from 74HC165
  read74hc165();
  // Set data to 74HC595
  write74hc595();
  }

  if (debug) printDebug();
  delay(500);
}

void read74hc165() {
  // Get data from 74HC165
  digitalWrite(clockEnable_lachSTCP, HIGH);
  digitalWrite(load, LOW);  
  digitalWrite(clockEnable_lachSTCP, LOW);
  digitalWrite(load, HIGH);  

  // Read dataIn and write data74hc165
  Serial.print("Reading 74hc165: ");
  for (int b = num74hc165Pins -1; b >= 0; b--) {
    int bit = digitalRead(dataIn);
    if (bit == HIGH) {
      Serial.print("1");
      bitWrite(data74hc165,b,HIGH);
    } else {
      Serial.print("0");
      bitWrite(data74hc165,b,LOW);
    }
    digitalWrite(clockIn_clockOut, HIGH); // Shift out the next bit
    digitalWrite(clockIn_clockOut, LOW);
  }

  if (data74hc165 != last74hc165) {
    for (int b = num74hc165Pins -1; b >= 0; b--) {
      if (bitRead(data74hc165, b) != bitRead(last74hc165, b)) {
        int pressed = bitRead(data74hc165, b);
        if (pressed) {
          bool data = (false == bitRead(data74hc595, b))?HIGH:LOW;
          bitWrite(data74hc595, b, data);
          Serial.print(" Altered Position: "); Serial.print(b+1); 
          Serial.print(" Data: "); Serial.print(data);
          startReadWrite = 0;
        }
      }
    }
    last74hc165 = data74hc165;
  }
}

void write74hc595() {
  // ST_CP LOW to keep LEDs from changing while reading serial data
  //if (data74hc595 != last74hc595) {
    // Shift out the bits
    shiftOut(dataOut, clockIn_clockOut, LSBFIRST, data74hc595);
    Serial.println(" Writing 74hc595 ");
    // ST_CP HIGH change LEDs
    digitalWrite(clockEnable_lachSTCP, HIGH);
    digitalWrite(load, LOW);
    digitalWrite(clockEnable_lachSTCP, LOW);
    digitalWrite(load, HIGH);    
    //last74hc595 = data74hc595;
  //}
}

void printDebug() {
    //Print data74hc165 byte
    //for (int b = 7; b >= 0; b--) Serial.print(bitRead(data74hc165, b)); 
    Serial.print("Data 74HC595: ");
    for (int b = num74hc595Pins -1; b >= 0; b--) Serial.print(bitRead(data74hc595, b));
    Serial.print(" Dec: ");
    Serial.print(data74hc595, DEC);    
    Serial.println();
}*/