/*

#############################################
||                                         ||
||                 Title:                  ||
||Simple Serial Read for 595 Shift Register||
||              Name: GC1CEO               ||
||            Date: 09/19/2024             ||
||              Adapted from:              ||
||         Shift Register Example          ||
||              By: Tom Igoe               ||
||            Date: 23 Mar 2010            ||
||                                         ||
||              Description:               ||
||                                         ||
||      Inputting a value from 0 to 7      ||
||       turns on the corresponding        ||
||                  LED.                   ||
||                                         ||
#############################################

*/

//Pin connected to ST_CP (Storage Clock / Latch) of 74HC595
int latchPin = 8;
//Pin connected to SH_CP (Shift Clock) of 74HC595
int clockPin = 12;
////Pin connected to DS / SER (Data/Serial Input) of 74HC595
int dataPin = 11;
////Pin connected to inverted MR / SRCLR (Master Reset / Serial Register Clear) of 74HC595
int resetPin = 10;
////Pin connected to inverted OE (Output Enable) of 74HC595
int oePin = 9;

void setup() {
Serial.begin(9600);
Serial.println("reset");
//set pins to output so you can control the shift register and setting button and pot pins to INPUT
pinMode(latchPin, OUTPUT);
pinMode(clockPin, OUTPUT);
pinMode(dataPin, OUTPUT);
pinMode(resetPin, OUTPUT);
pinMode(oePin, OUTPUT);


// Setting reset to HIGH to stop reset and setting output enable to LOW to always enable output
digitalWrite(resetPin, HIGH);
digitalWrite(oePin, LOW);

// Cleaning up serial monitor and announcing program has initalized and going to loop
for(int a = 0; a < 25; a++){
  Serial.println();
}

Serial.println("Please enter a number from 0 to 7.");

}
void loop() {

if (Serial.available() > 0) {

// ASCII '0' through '9' characters are
// represented by the values 48 through 57.
// so if the user types a number from 0 through 9 in ASCII,
// you can subtract 48 to get the actual value:

  int bitToSet = Serial.read() - 48;
  Serial.println(bitToSet);

// write to the shift register with the correct bit set high:

  registerWrite(bitToSet, HIGH);

}

}

// This method sends bits to the shift register:

void registerWrite(int whichPin, int whichState) {

  // the bits you want to send

  byte bitsToSend = 0;

  // turn off the output so the pins don't light up

  // while you're shifting bits:

  digitalWrite(latchPin, LOW);

  // turn on the next highest bit in bitsToSend:

  bitWrite(bitsToSend, whichPin, whichState);

  // shift the bits out:

  shiftOut(dataPin, clockPin, MSBFIRST, bitsToSend);

  // turn on the output so the LEDs can light up:

  digitalWrite(latchPin, HIGH);

}