// MNEMONICS FOR BUTTONS
   // MNEMONICS FOR LCD
   #define   lcd_rs   PIN_B0
   #define   lcd_rw   PIN_B1
   #define   lcd_e   PIN_B2
   #define   lcd_cmd_wri   0x00
   #define   lcd_data_wri   0x01
   #define   lcd_busy_rd   0x02
   #define   lcd_set_function   0x38   //8 bit interface, 2 line mode, 5x7 dot format
   #define   lcd_set_visible   0x0F   //Display on, cursor underline on, cursor blink on
   #define   lcd_set_shift   0x16   //Cursor move, Right shift
   #define   lcd_set_mode   0x06   //Increment, display shift off
   #define   lcd_set_cgaddr   0x40
   #define   lcd_set_ddaddr   0x80
   #define   lcd_clr   0x01
   #define   lcd_init   0x30
   #define   NULL   0
   #include "D:\Pic16F877\MyProject\Doit\MainDoit\Doit.h"


void LcdEnable();
void WrCmd2Lcd(int cmd);
void WrDat2Lcd(int data);
void InitLcd();
void Speech(int *words,int position);
void LcdWait();
int OnRelease();
void main()
{
   //INTRO OR GUIDED WORDS
   int hello[]="HELLO WORLD! ";
   int keyPressed,key;
   int array[16]={0x31,0x34,0x37,0x3C,0x32,0x35,0x38,0x30,0x33,0x36,0x39,0x3E,0x43,0x26,0x45,0x4D};
   //PIC SET-UP PARAMETERS
   setup_adc_ports(NO_ANALOGS);
   setup_adc(ADC_OFF);
   setup_psp(PSP_DISABLED);
   setup_spi(FALSE);
   setup_timer_0(RTCC_INTERNAL|RTCC_DIV_1);
   setup_timer_1(T1_DISABLED);
   setup_timer_2(T2_DISABLED,0,1);
   setup_comparator(NC_NC_NC_NC);
   setup_vref(FALSE);
   // TODO: USER CODE!!
   set_tris_b(0x00);
   set_tris_c(0x00);
   InitLcd();
   delay_ms(1000);
   WrDat2Lcd(array[1]);
   key=2;
   WrDat2Lcd(array[key]);
   WrDat2Lcd('A');
   WrDat2Lcd('B');
   Speech(hello,lcd_set_ddaddr+0x40);
   play:
   keyPressed=OnRelease();
   if (keyPressed == -1)
   goto play;
   WrDat2Lcd(array[keyPressed]); 
// I press '1' button, a square dark appear, 
// but if I add WrDat2Lcd('any one char here') after WrDat2Lcd(array[keyPressed]);  
// then when I press '1' button, 
// a square dark and the next number '1' appear on screen, could anyone explain me this phenomenon ? Thanks !!!
   goto play;
}
//----------------------
void LcdEnable()
{
   output_high(lcd_e);
   output_low(lcd_e);
}
//----------------------
void WrCmd2Lcd(int cmd)
{
   set_tris_d(0x00);
   output_high(lcd_rs);
   output_low(lcd_rs);
   output_d(cmd);
   LcdEnable();
}
//----------------------
void WrDat2Lcd(int data)
{
   set_tris_d(0x00);
   output_high(lcd_rs);
   output_low(lcd_rs);
   output_d(data);
   LcdEnable();
   output_high(lcd_e);
}
//----------------------
void InitLcd()
{
   set_tris_d(0x00);
   output_low(lcd_rs);   //added
   output_low(lcd_rw);   //added
   output_low(lcd_e);
   delay_ms(125);
   WrCmd2Lcd(lcd_init);
   delay_ms(20);
   LcdEnable();
   delay_us(200);
   LcdEnable();
   delay_us(100);
   WrCmd2Lcd(lcd_set_function);
   delay_ms(10);
   WrCmd2Lcd(lcd_set_visible);
   delay_ms(10);
   WrCmd2Lcd(lcd_clr);
   delay_us(100);
   WrCmd2Lcd(lcd_set_ddaddr);
   delay_us(100);
}
//-------------------------
void Speech(int *words,int position)
{
   int *textptr;
   textptr = words;
   WrCmd2Lcd(position);
   do
   {
   WrDat2Lcd(*textptr);
   *textptr++;
   }
   while(*textptr != '\0');
}
//----------------------
void LcdWait()
{
   int status;
   set_tris_d(0xFF);
   output_high(lcd_rw);
   do
   {
      status=input_d();
      LcdEnable();
   }
   while(status & 0x80);   // test busy flag.
}
//-------------------------
int OnRelease()
{
   int i,j,k;
   int value[4]={0x07,0x0B,0x0D,0x0E};
   set_tris_a(0x0f);
   set_tris_d(0xf0);
   k=0;
   for(i=0;i<4;i++)
   {
      output_d(value[i]);
      delay_us(100);
      for(j=0;j<4;j++)
      {
         if(!input(40+j))
         {
            do
            {
               delay_ms(400);
            }
            while(!input(40+j));
            return k;
         }
         else
            k++;
      }
   }
   return -1;
}