//////////////////////////////////////////////////////
//   This program demonstrates a Master and slave 
//   communication using I2C interface of LPC2148
//   In this example Master is LPC2148 device 
//   and slave is a I2CtoLCD converter PCF8574
//   Author: RGK
//////////////////////////////////////////////////////

#include<lpc213x.h>
#include<string.h>

////////////////////////
#define SLAVE_ADDR 0x70     
#define MAX        12
#define AA         2
#define SI         3
#define STO        4
#define STA        5
#define I2EN       6

////////////////////////////
//         Delay Function
//
wait(int count){
      while(count-- );
}
//////////////////////////
//        Initialize I2c
//
//
//
void I2C_Init (void)
{
   VPBDIV    =   0x02;        // sets FOSC =  60MHHZ
   PINSEL0   =   0x00000050;  // set po.2,p0.3 to sda scl
   
   I2C0SCLH   =   150;        //50%duty,I2CFreq->100KHz,PCLK=30MHz
   I2C0SCLL   =   150;

   I2C0CONSET  =  (1<<I2EN);  //Enable I2C module
}
//////////////////////////
//     Enter Master 
//     transmitter Mode
//
int I2C_Start ()
{
   I2C0CONCLR   =   1 << STO; 
   I2C0CONCLR = 1 << SI;   
   I2C0CONSET   =   1 << STA; 
   return 0;
}

//////////////////////////////////////
//      Delay function
//
//
void delay_ms(int count)
{
  int j=0,i=0;
 
  for(j=0;j<count;j++)
  {
    /* At 60Mhz, the below loop introduces
    delay of 10 us */
    for(i=0;i<35;i++);
  }
}
///////////////////////////////////////////////////////
//      Function to send data from Master to slave I2C
//      device
//
void senddata(char data){ 
     while(!(I2C0CONSET & 0x08)); 		 
		 I2C0DAT      =   data; 
		 I2C0CONCLR   =   1 << SI;
		 delay_ms(200);
} 
///////////////////////////////////////////////////
//      Function to send a byte of char data
//      EX:if data = 0x12 higher nibble 
//      is sent first in this case 0x1 and then lower
//      nibble.whyy? Because slave is set to 4bit mode.
//      The Format shud be :7  6   5  4 3 2 1 0
//                          0  RS RW  E|D A T A
//
void sendchar(char data){     
	 
	   senddata(0x50 | (data>>4));delay_ms(50);
	   senddata(0x40 | (data>>4));delay_ms(50);
		 senddata(0x50 | (data&0x0f)); delay_ms(50);
	   senddata(0x40 | (data& 0x0f));delay_ms(50);
		 delay_ms(50);
} 

int main(){
	
		  char code =  SLAVE_ADDR;// 0x6e;
		  
		  char i2cdev[] = "LCD DISPLAY ON";
		  int i =0;

		  I2C_Init();                  //Initialize I2C moodule		
			I2C_Start();                 //start I2C module 
     	wait(4000);

			while(!(I2C0CONSET & 0x08)); //wait till SI bit set
			IO0SET = (1<<21);
      I2C0CONCLR	 =	 1 << STO;
			I2C0CONCLR	 =	 1 << STA;				
			I2C0CONSET   =   1 << AA;
			I2C0DAT      =  code;
			
			I2C0CONCLR   =   1 << SI; 
			//wait(4000);	
			while(!(I2C0CONSET & 0x08));
			if(I2C0STAT == 0x18)
			{	  
					 IO0SET = (1<<23);	  	   	 
				   I2C0CONSET   =   1 << AA;
					 I2C0DAT      =   0x00;//x00;//Buff[index]; 
				   I2C0CONCLR   =   1 << SI; 
				   while(!(I2C0CONSET & 0x08));
					 for(i=0; i < 2000;i++)wait(800);
				   if(I2C0STAT == 0x28)
					 {		 

             //SEND LCD INITIALIING COMMANDS TO SET LCD MODULE IN 4 BIT ,5X7,2 LINES							
						   
						 senddata(0x10);         //TOGGEL ENABLE PIN 
						 senddata(0x00);	       //TOGGEL ENABLE PIN WITH DATA		 
						 		 
						 senddata(0x12);		  
						 senddata(0x02);				
						 
						 senddata(0x12);
						 senddata(0x02);
					
						 
						 senddata(0x18);
						 senddata(0x08);
					 
						 senddata(0x10);
						 senddata(0x00);
						 
						 senddata(0x1e);
						 senddata(0x0e);
								
						 senddata(0x10);
						 senddata(0x00);		  
						
						 senddata(0x16);
						 senddata(0x06);					
						
						 senddata(0x10);
						 senddata(0x00);
						
						 senddata(0x11);
						 senddata(0x01);				 
						
						 senddata(0x18);
						 senddata(0x08);	  
						
						 senddata(0x10);
						 senddata(0x00);
					
					
					   //SEND YOUR DISPLAYY STRING
					   while(1){
							    i = 0;
							    while(i2cdev[i] !='\0'){
								       sendchar(i2cdev[i]);
								       i++;
							    }									
							    senddata(0x10);
							    senddata(0x00);							
							    senddata(0x11);
							    senddata(0x01);
						 }					
			    }			
			}
}//END OF MAIN