#include <avr/io.h>
#include <util/delay.h>
#include <stdlib.h>
#include <stdint.h>
typedef uint8_t bits_type;
//defines IOs 
#define CFG_SHIFT_DDR DDRD
#define CFG_SHIFT_PORT PORTD
#define CFG_SHIFT_SRCLK PD3 //arduino pin 3 for Clock
#define CFG_SHIFT_RCLK PD4 //arduino pin 4 for Latch
#define CFG_SHIFT_SER PD2 //arduino pin 2 for Data
//number of pins in the shift register
#define CFG_SHIFT_REGISTER_PIN_COUNT 8

void shift_bits_init(void);
void shift_bits_out(bits_type b, size_t len);
//void LCDinit();
//void LCDprint(char _line, char _string[16]);

void shift_bits_init(void)
{
  CFG_SHIFT_DDR |= _BV(CFG_SHIFT_RCLK)
            | _BV(CFG_SHIFT_SRCLK)
            | _BV(CFG_SHIFT_SER);
}

void shift_bits_out(bits_type b, size_t len)
{
      CFG_SHIFT_PORT &= ~_BV(CFG_SHIFT_RCLK);
      for (size_t i = 0; i < CFG_SHIFT_REGISTER_PIN_COUNT; i++){
            CFG_SHIFT_PORT &= ~_BV(CFG_SHIFT_SRCLK);
            if(i < len && (b & ((bits_type)1 << i)))
                    CFG_SHIFT_PORT |= _BV(CFG_SHIFT_SER);
            CFG_SHIFT_PORT |= _BV(CFG_SHIFT_SRCLK);
            CFG_SHIFT_PORT &= ~_BV(CFG_SHIFT_SER);
      }
      CFG_SHIFT_PORT |= _BV(CFG_SHIFT_RCLK);
}

void LCDSendByte(char d,char RS)
{
  char dH,dL,temp;
//Keep Data on upper nybble
  dH = d & 0xF0;         //Get MSB
  dL = d & 0x0F;
  dL = d << 4;           //Get LSB
//Send MSB with E=clock  
  temp=0;
  temp=dH | RS | 0x02;  //MSB With RS+E bit
  shift_bits_out(temp, 8);
//Send MSB with E=0
  temp=0;
  temp=dH | RS;  //MSB With RS bit
  shift_bits_out(temp, 8);
//Send LSB with E=clock
  temp=0;
  temp=dL | RS | 0x02;  //MSB With RS+E bit
  shift_bits_out(temp, 8);
//Send LSB with E=0
  temp=0;
  temp=dL | RS;  //MSB With RS bit
  shift_bits_out(temp, 8);
}

void LCDInit()
{
  int count;
  char t[] = {0x43,0x03,0x03,0x02,0x28,0x01,0x0C,0x06,0x02,0x02};
  for(count = 0; count <=9; count ++)
  {
    LCDSendByte(t[count],0);  //command=0;
  }
}
void LCDPrint(char line, char string[16])
{
  int len,count;
  if(line==0){
    LCDSendByte(0x80,0); //RS = 0 Move Cursor to home
  }
  else{
    LCDSendByte(0xC0,0); //RS = 0 Move Cursor to Second Line
  }
  len = strlen(string);
  for(count=0;count<len;count++)
  {
    LCDSendByte(string[count],1);
  }
}

int main()
{
  shift_bits_init();
  LCDInit();
  _delay_ms(1000);    
  while(1)
  {
    LCDPrint(0, "Hello There");
    LCDPrint(1, "was hard !");
    _delay_ms(500);
  }
  return 0;
}