afnan.bashir
Member
I have been trying to interface 16x2 lcd but failing. I am new to MPLAB so its sort of frustrating. I searched various forums so it came to my knowledge that xc8 has plib so i can use xlcd.h for my intentions.
Now the problem is the program compiles fine. But there is nothing on lcd and not even the lcd pins toggle. I added PORTC toggle to see if my code is working and it was. Onlything that is not working is LCD.
After changing the PIN configuration in xlcd.h i included it in project also pic18f452.h and recompiled and there was success building it too. Please see the code and proteus image to help me out.
xlcd.h
main.c
Now the problem is the program compiles fine. But there is nothing on lcd and not even the lcd pins toggle. I added PORTC toggle to see if my code is working and it was. Onlything that is not working is LCD.
After changing the PIN configuration in xlcd.h i included it in project also pic18f452.h and recompiled and there was success building it too. Please see the code and proteus image to help me out.
xlcd.h
Code:
#ifndef __XLCD_H
#define __XLCD_H
#include "p18cxxx.h"
/* PIC18 XLCD peripheral routines.
*
* Notes:
* - These libraries routines are written to support the
* Hitachi HD44780 LCD controller.
* - The user must define the following items:
* - The LCD interface type (4- or 8-bits)
* - If 4-bit mode
* - whether using the upper or lower nibble
* - The data port
* - The tris register for data port
* - The control signal ports and pins
* - The control signal port tris and pins
* - The user must provide three delay routines:
* - DelayFor18TCY() provides a 18 Tcy delay
* - DelayPORXLCD() provides at least 15ms delay
* - DelayXLCD() provides at least 5ms delay
*/
/* Interface type 8-bit or 4-bit
* For 8-bit operation uncomment the #define BIT8
*/
/* #define BIT8 */
/* When in 4-bit interface define if the data is in the upper
* or lower nibble. For lower nibble, comment the #define UPPER
*/
/* #define UPPER */
/* DATA_PORT defines the port to which the LCD data lines are connected */
#define DATA_PORT PORTB
#define TRIS_DATA_PORT TRISB
/* CTRL_PORT defines the port where the control lines are connected.
* These are just samples, change to match your application.
*/
#define RW_PIN LATBbits.LATB6 /* PORT for RW */
#define TRIS_RW TRISBbits.TRISB6 /* TRIS for RW */
#define RS_PIN LATBbits.LATB4 /* PORT for RS */
#define TRIS_RS DDRBbits.TRISB4 /* TRIS for RS */
#define E_PIN LATBbits.LATB5 /* PORT for D */
#define TRIS_E DDRBbits.TRISB5 /* TRIS for E */
/* Display ON/OFF Control defines */
#define DON 0b00001111 /* Display on */
#define DOFF 0b00001011 /* Display off */
#define CURSOR_ON 0b00001111 /* Cursor on */
#define CURSOR_OFF 0b00001101 /* Cursor off */
#define BLINK_ON 0b00001111 /* Cursor Blink */
#define BLINK_OFF 0b00001110 /* Cursor No Blink */
/* Cursor or Display Shift defines */
#define SHIFT_CUR_LEFT 0b00000100 /* Cursor shifts to the left */
#define SHIFT_CUR_RIGHT 0b00000101 /* Cursor shifts to the right */
#define SHIFT_DISP_LEFT 0b00000110 /* Display shifts to the left */
#define SHIFT_DISP_RIGHT 0b00000111 /* Display shifts to the right */
/* Function Set defines */
#define FOUR_BIT 0b00101100 /* 4-bit Interface */
#define EIGHT_BIT 0b00111100 /* 8-bit Interface */
#define LINE_5X7 0b00110000 /* 5x7 characters, single line */
#define LINE_5X10 0b00110100 /* 5x10 characters */
#define LINES_5X7 0b00111000 /* 5x7 characters, multiple line */
#ifdef _OMNI_CODE_
#define PARAM_SCLASS
#else
#define PARAM_SCLASS auto
#endif
#ifndef MEM_MODEL
#ifdef _OMNI_CODE_
#define MEM_MODEL
#else
#define MEM_MODEL far /* Change this to near for small memory model */
#endif
#endif
/* OpenXLCD
* Configures I/O pins for external LCD
*/
void OpenXLCD(PARAM_SCLASS unsigned char);
/* SetCGRamAddr
* Sets the character generator address
*/
void SetCGRamAddr(PARAM_SCLASS unsigned char);
/* SetDDRamAddr
* Sets the display data address
*/
void SetDDRamAddr(PARAM_SCLASS unsigned char);
/* BusyXLCD
* Returns the busy status of the LCD
*/
unsigned char BusyXLCD(void);
/* ReadAddrXLCD
* Reads the current address
*/
unsigned char ReadAddrXLCD(void);
/* ReadDataXLCD
* Reads a byte of data
*/
char ReadDataXLCD(void);
/* WriteCmdXLCD
* Writes a command to the LCD
*/
void WriteCmdXLCD(PARAM_SCLASS unsigned char);
/* WriteDataXLCD
* Writes a data byte to the LCD
*/
void WriteDataXLCD(PARAM_SCLASS char);
/* putcXLCD
* A putc is a write
*/
#define putcXLCD WriteDataXLCD
/* putsXLCD
* Writes a string of characters to the LCD
*/
void putsXLCD(PARAM_SCLASS char *);
/* putrsXLCD
* Writes a string of characters in ROM to the LCD
*/
void putrsXLCD(const char *);
/* User defines these routines according to the oscillator frequency */
extern void DelayFor18TCY(void);
extern void DelayPORXLCD(void);
extern void DelayXLCD(void);
#endif
main.c
Code:
#include <p18cxxx.h>
#include <plib/xlcd.h>
#include <delays.h>
#include <xc.h>
/* Set configuration bits for use with ICD2 / PICDEM2 PLUS Demo Board:
* - set HS oscillator
* - disable watchdog timer
* - disable low voltage programming
*/
#pragma config OSC = HS
#pragma config WDT = OFF
#pragma config LVP = OFF
#define _XTAL_FREQ 20000000UL
void DelayFor18TCY(void)
{
Delay10TCYx(0x2); //delays 20 cycles
return;
}
/*****/
void DelayPORXLCD(void) // minimum 15ms
{
Delay100TCYx(0xA0); // 100TCY * 160
return;
}
/*****/
void DelayXLCD(void) // minimum 5ms
{
Delay100TCYx(0x36); // 100TCY * 54
return;
}
void main(){
PORTC = 0X00;
TRISC = 0X00;
OpenXLCD(FOUR_BIT & LINES_5X7);
WriteDataXLCD('H');
WriteCmdXLCD(DON&CURSOR_OFF&BLINK_OFF);
while(1)
{
PORTC=~PORTC; //LED off for a short time to show we are looping
while(BusyXLCD());
Delay10KTCYx(250);
putrsXLCD("Lcd Testing..");
}
}
**broken link removed**