//Routine output data to LCD in 4 bit mode.
//
//with the choice of assigning the data bits to the top nibble or bottom		
//nibble of the data port.   
//Rs and Enable can be on seperate ports. /WR is not used and should be 
//hardwired to Ov.
//
//
//
//
//
//   port for enable and rs may be changed by appropriate port declaration
//
//**copyright C D Barnard  7/10/2002 Version 1.0
//
//


#include <lcd_shiftout.h>
#include <delays.h>

//These must be included because of the #ifdef declarations
#asmfunc lcd_num(conv,digit)
#asmfunc num2hex(decimal)
#asmfunc lcd_hex(dec)
#asmfunc lcd_st(*string) 
//****************************************************************


unsigned char rs_state;


void lcd_packet(unsigned char raw_data,unsigned char rs_state)
{

  #ifdef TOP
     LCDPORT&=0x0F;                     //Clear top bits 
     lcd_out(raw_data&0xF0,rs_state);   //Send high nibble
     lcd_out(raw_data<<4,rs_state);     //Swap byte and send low nibble
     Wait(10);				//delay between data bytes
  #else
     LCDPORT&=0xF0;                     //Clear bottom bits 
     lcd_out(raw_data&0x0F,rs_state); 
     lcd_out(raw_data>>4,rs_state);
     Wait(10);			

  #endif 
}



void lcd_out(unsigned char lcd_data,unsigned char inst)
{
  unsigned char bitmask;
	
  bitmask=1<<rsbit;
  
  LCDPORT=lcd_data;
  if(inst&1)
   {
    RSPORT|=bitmask;
   }
  else
   {
    RSPORT&=~bitmask;
   } 
  ENPORT^=1<<ebit;
  #asmline nop
  ENPORT^=1<<ebit;

}

  
 //End of write routines 
//**********************************************************************

//General Lcd routines

#ifdef _lcd_init
void lcd_init(void)
{
   //wake LCD,4bit mode/5*8font,clear,home,disp on/cursor off blink off 
   const unsigned char initialise[6]={0x33,0x32,0x28,0x01,0x02,0x0C};
   unsigned char loop;
   
   rs_state=0;				  //lcd in command mode
   
   Wait(20);				  //wait 20mS for LCD to power up	
   for (loop=0;loop<6;loop++)
   {
     lcd_packet(initialise[loop],rs_state);
     Wait(1);				//Wait 1mS between initialising bytes	
   }
   rs_state=1;
   
}
#endif

#ifdef _lcd_clear
void lcd_clear()
{
 rs_state=0; 			//command mode
 
 lcd_packet(0x08,rs_state);	// Display off
 lcd_packet(0x01,rs_state);	// Clear display
 lcd_packet(0x0C,rs_state);	// Display on
 lcd_packet(0x80,rs_state);	//  Print at 0,0
 rs_state=1;
}
#endif

#ifdef _lcd_pos
void lcd_pos(unsigned char line,unsigned char column)
{
 //upto 4*16 display, change 0x90->0x94 and 0xD0->0xD4 for 4*20 display
 
    const unsigned char row[4]={0x80,0xC0,0x90,0xD0};
 
    rs_state=0; 			//command mode
    line-=1;			 	//adjust for human maths
    
    lcd_packet((row[line] + column),rs_state);	//row + column required
    rs_state=1;  
    Wait(1);
}
#endif

#ifdef _lcd_st
void lcd_st(unsigned char *string)
{
   
    rs_state=1;			//data mode
    
   while(*string)		//while not end of string
   {
     	
    
     lcd_packet(*string,rs_state);
     ++string; 		//move to next character
   }
   
}
#endif

#ifdef _lcd_hex
void lcd_hex(unsigned char dec)
{
   unsigned char hexnum;
   
   rs_state=1;			 //data mode
   
   hexnum=num2hex(dec>>4);		//convert decimal number
   lcd_packet(hexnum,rs_state); // pump it out
   hexnum=num2hex(dec&0x0F);
   lcd_packet(hexnum,rs_state);
}
#endif

#ifdef _lcd_num
//Converts decimal numbers to 9999 to ASCII 
void lcd_num(unsigned int conv, unsigned char digit,unsigned char lz)
{
 
  
   unsigned int temp1,decnum;
   unsigned char hexnum;
   rs_state=1;					//data mode
       
        if(digit==4)
         {
	   decnum=conv/1000 ; 	//get the thousands
	   hexnum=lzero(decnum,lz);      //leading blank
	  // hexnum=num2hex(decnum);	//convert to ASCII hex
	   lcd_packet(hexnum,rs_state);
	 }
	  
	
	
	if(digit>2)
	 {  
 	   	//workout the remainder
 	   conv=conv%1000;
 	   decnum=conv/100;		//get the hundreds
 	   hexnum=lzero(decnum,lz);
 	 //  hexnum=num2hex(decnum);
 	      
 	   lcd_packet(hexnum,rs_state);
 	  
 	}
 	
 	if(digit>1)
 	 {
 	   conv=conv%100;
 	   decnum=conv/10;		//get the tens
 	   hexnum=lzero(decnum,lz);
 	 //  hexnum=num2hex(decnum);
 	   lcd_packet(hexnum,rs_state);
 	   lz=0;
 	 }
 	 
 	
 	 decnum=conv%10;
 	 hexnum=num2hex(decnum);		//the units
 	 lcd_packet(hexnum,rs_state);
        
}
#endif

#ifdef _num2hex
unsigned char num2hex(unsigned char decimal)
{
   unsigned char temp;
   
   if (decimal < 10)
     { 
       temp= decimal+'0';        //if number less than 10 add 30h for ASCII No.
     }
   else 
     {
        temp=decimal-10;	//Number greater than ten add 41h  
        temp+= 'A';		//to get number in hex
     }
     
   return (temp);

}
#endif

#ifdef _lzero
unsigned char lzero(unsigned char decimal, unsigned char showz)
{
  if(decimal==0 && showz)
   return 0x20;
  else
   return num2hex(decimal);
}
#endif