PicLcd4BitCmdWrite.c

/* Function to send the command to LCD. 
   As it is 4bit mode, a byte of data is sent in two 4-bit nibbles */
void Lcd_CmdWrite(char cmd)
{
    LcdDataBus = (cmd & 0xF0);     //Send higher nibble
    LcdControlBus &= ~(1<<LCD_RS); // Send LOW pulse on RS pin for selecting Command register
    LcdControlBus &= ~(1<<LCD_RW); // Send LOW pulse on RW pin for Write operation
    LcdControlBus |= (1<<LCD_EN);  // Generate a High-to-low pulse on EN pin
    delay(1000);
    LcdControlBus &= ~(1<<LCD_EN);

    delay(10000);

    LcdDataBus = ((cmd<<4) & 0xF0); //Send Lower nibble
    LcdControlBus &= ~(1<<LCD_RS);  // Send LOW pulse on RS pin for selecting Command register
    LcdControlBus &= ~(1<<LCD_RW);  // Send LOW pulse on RW pin for Write operation
    LcdControlBus |= (1<<LCD_EN);   // Generate a High-to-low pulse on EN pin
    delay(1000);
    LcdControlBus &= ~(1<<LCD_EN); 

    delay(10000);
}