/********************************************************************
16X2 ALPHANEUMERIC LCD INTERFACING LIBRARY FOR PIC 18F MCUS
-----------------------------------------------------------
Easy to use library for interfacing 16x2 lcd in 4 bit mode.
MCU: PIC18FXXXX Series from Microchip.
Compiler: HI-TECH C Compiler for PIC18 MCUs (
https://www.htsoft.com/)
Copyrights 2008-2009 Avinash Gupta
eXtreme Electronics, India
For More Info visit
https://www.eXtremeElectronics.co.in
Mail:
me@avinashgupta.com
********************************************************************/
#include <htc.h>
#include <string.h>
#include <ctype.h>
#include <pic18.h>
#include <stdlib.h>
#include <stdio.h>
#include "lcd.h"
#define LCD_DATA_LAT LAT(LCD_DATA)
#define LCD_E_LAT LAT(LCD_E)
#define LCD_RS_LAT LAT(LCD_RS)
#define LCD_RW_LAT LAT(LCD_RW)
#define LCD_DATA_TRIS TRIS(LCD_DATA)
#define LCD_E_TRIS TRIS(LCD_E)
#define LCD_RS_TRIS TRIS(LCD_RS)
#define LCD_RW_TRIS TRIS(LCD_RW)
#define LCD_DATA_PORT PORT(LCD_DATA)
#define SET_E() (LCD_E_LAT|=(1<<LCD_E_POS))
#define SET_RS() (LCD_RS_LAT|=(1<<LCD_RS_POS))
#define SET_RW() (LCD_RW_LAT|=(1<<LCD_RW_POS))
#define CLEAR_E() (LCD_E_LAT&=(~(1<<LCD_E_POS)))
#define CLEAR_RS() (LCD_RS_LAT&=(~(1<<LCD_RS_POS)))
#define CLEAR_RW() (LCD_RW_LAT&=(~(1<<LCD_RW_POS)))
void LCDByte(uint8_t c,uint8_t isdata)
{
//Sends a byte to the LCD in 4bit mode
//cmd=0 for data
//cmd=1 for command
//NOTE: THIS FUNCTION RETURS ONLY WHEN LCD HAS PROCESSED THE COMMAND
uint8_t hn,ln; //Nibbles
uint8_t temp;
hn=c>>4;
ln=(c & 0x0F);
if(isdata==0)
CLEAR_RS();
else
SET_RS();
__delay_us(0.500); //tAS
SET_E();
//Send high nibble
temp=(LCD_DATA_LAT & 0XF0)|(hn);
LCD_DATA_LAT=temp;
__delay_us(1); //tEH
//Now data lines are stable pull E low for transmission
CLEAR_E();
__delay_us(1);
//Send the lower nibble
SET_E();
temp=(LCD_DATA_LAT & 0XF0)|(ln);
LCD_DATA_LAT=temp;
__delay_us(1); //tEH
//SEND
CLEAR_E();
__delay_us(1); //tEL
LCDBusyLoop();
}
void LCDBusyLoop()
{
//This function waits till lcd is BUSY
uint8_t busy,status=0x00,temp;
//Change Port to input type because we are reading data
LCD_DATA_TRIS|=0x0F;
//change LCD mode
SET_RW(); //Read mode
CLEAR_RS(); //Read status
//Let the RW/RS lines stabilize
__delay_us(0.5); //tAS
do
{
SET_E();
//Wait tDA for data to become available
__delay_us(0.5);
status=LCD_DATA_PORT;
status=status<<4;
__delay_us(0.5);
//Pull E low
CLEAR_E();
__delay_us(1); //tEL
SET_E();
__delay_us(0.5);
temp=LCD_DATA_PORT;
temp&=0x0F;
status=status|temp;
busy=status & 0b10000000;
__delay_us(0.5);
CLEAR_E();
__delay_us(1); //tEL
}while(busy);
CLEAR_RW(); //write mode
//Change Port to output
LCD_DATA_TRIS&=0xF0;
}
void LCDInit(uint8_t style)
{
/*****************************************************************
This function Initializes the lcd module
must be called before calling lcd related functions
Arguments:
style = LS_BLINK,LS_ULINE(can be "OR"ed for combination)
LS_BLINK :The cursor is blinking type
LS_ULINE :Cursor is "underline" type else "block" type
*****************************************************************/
//After power on Wait for LCD to Initialize
__delay_ms(30);
//Set IO Ports
LCD_DATA_TRIS&=(0xF0);
LCD_E_TRIS&=(~(1<<LCD_E_POS));
LCD_RS_TRIS&=(~(1<<LCD_RS_POS));
LCD_RW_TRIS&=(~(1<<LCD_RW_POS));
LCD_DATA_LAT&=0XF0;
CLEAR_E();
CLEAR_RW();
CLEAR_RS();
//Set 4-bit mode
__delay_us(0.3); //tAS
SET_E();
LCD_DATA_LAT|=(0b00000010); //
To transfer 0b00100000 i was using LCD_DATA_PORT|=0b00100000
__delay_us(1);
CLEAR_E();
__delay_us(1);
//Wait for LCD to execute the Functionset Command
LCDBusyLoop(); // Forgot this delay
//Now the LCD is in 4-bit mode
LCDCmd(0b00001100|style); //Display On
LCDCmd(0b00101000); //function set 4-bit,2 line 5x7 dot format
}
void LCDWriteString(const char *msg)
{
/*****************************************************************
This function Writes a given string to lcd at the current cursor
location.
Arguments:
msg: a null terminated string to print
*****************************************************************/
while(*msg!='\0')
{
LCDData(*msg);
msg++;
}
}
void LCDWriteInt(int val,unsigned int field_length)
{
/***************************************************************
This function writes a integer type value to LCD module
Arguments:
1)int val : Value to print
2)unsigned int field_length :total length of field in which the value is printed
must be between 1-5 if it is -1 the field length is no of digits in the val
****************************************************************/
char str[5]; ={0,0,0,0,0};
int i=4,j=0;
while(val)
{
str=val%10;
val=val/10;
i--;
}
if(field_length==-1)
while(str[j]==0) j++;
else
j=5-field_length;
if(val<0) LCDData('-');
for(i=j;i<5;i++)
{
LCDData(48+str);
}
}
void LCDGotoXY(uint8_t x,uint8_t y)
{
if(x<40)
{
if(y) x|=0b01000000;
x|=0b10000000;
LCDCmd(x);
}
}