Interfacing LCD display to PORTC(PIC18f2431)

[Cantafford]

Hey,

I'm trying to use connect an LCD to PORTC of PIC18f2431. So far I have been only connecting LCD's to PORTB when using PICs which is assigned by default.

So I modified the contents of the "xlcd.h" file as this:

#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             PORTC
#define TRIS_DATA_PORT         TRISC

/* CTRL_PORT defines the port where the control lines are connected.
* These are just samples, change to match your application.
*/
#define RW_PIN   LATCbits.LATC6           /* PORT for RW */
#define TRIS_RW  TRISCbits.TRISC6       /* TRIS for RW */

#define RS_PIN   LATCbits.LATC5           /* PORT for RS */
#define TRIS_RS  TRISCbits.TRISC5       /* TRIS for RS */

#define E_PIN    LATCbits.LATC4         /* PORT for D  */
#define TRIS_E   TRISCbits.TRISC4       /* 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

I also included the files from " C:\Program Files (x86)\Microchip\xc8\v1.30\include\plib" to my project.

Then wrote this code that's supposed to display some simple text on the lcd:

#include <stdio.h>
#include <stdlib.h>
#include "header.h"
#include <plib/delays.h>
#include <plib/xlcd.h>


void init_XLCD(void);              //Initialize LCD display
void DelayFor18TCY( void );        //18 cycles delay
void DelayPORXLCD (void);          // Delay of 15ms
void DelayXLCD (void);             // Delay of 5ms

void main(void)
{
  
SCS1 = 0;
SCS0 = 0; // select primary oscillator

    init_XLCD();                    //Call the Initialize LCD display function

    putrsXLCD("Some");          //Display some text
    SetDDRamAddr(0x40);            //shift cursor to beginning of second line
    putrsXLCD("text");      // display some text

    while(1)
    {

    }
}

void init_XLCD(void)                //Initialize LCD display
{
OpenXLCD(FOUR_BIT&LINES_5X7);       //configure LCD in 4-bit Data Interface mode
                                    //and 5x7 characters, multiple line display
while(BusyXLCD());                  //Check if the LCD controller is not busy
                                    //before writing some commands
WriteCmdXLCD(0x06);                 //Move cursor right, don't shift display
WriteCmdXLCD(0x0C);                 //Turn display on without cursor
}

void DelayFor18TCY( void )         //18 cycles delay
{
Delay10TCYx(20);
}
void DelayPORXLCD (void)           //Delay of 15ms
{
Delay1KTCYx(30);
}
void DelayXLCD (void)              //Delay of 5ms
{
Delay1KTCYx(10);
}

The header.h is:

// PIC18F2431 Configuration Bit Settings

// 'C' source line config statements

#include <xc.h>

// #pragma config statements should precede project file includes.
// Use project enums instead of #define for ON and OFF.

// CONFIG1H
#pragma config OSC = XT         // Oscillator Selection bits (XT oscillator)
#pragma config FCMEN = OFF      // Fail-Safe Clock Monitor Enable bit (Fail-Safe Clock Monitor disabled)
#pragma config IESO = ON        // Internal External Oscillator Switchover bit (Internal External Switchover mode enabled)

// CONFIG2L
#pragma config PWRTEN = OFF     // Power-up Timer Enable bit (PWRT disabled)
#pragma config BOREN = OFF      // Brown-out Reset Enable bits (Brown-out Reset disabled)
// BORV = No Setting

// CONFIG2H
#pragma config WDTEN = OFF      // Watchdog Timer Enable bit (WDT disabled (control is placed on the SWDTEN bit))
#pragma config WDPS = 32768     // Watchdog Timer Postscale Select bits (1:32768)
#pragma config WINEN = OFF      // Watchdog Timer Window Enable bit (WDT window disabled)

// CONFIG3L
#pragma config PWMPIN = OFF     // PWM output pins Reset state control (PWM outputs disabled upon Reset (default))
#pragma config LPOL = HIGH      // Low-Side Transistors Polarity (PWM0, 2, 4 and 6 are active-high)
#pragma config HPOL = HIGH      // High-Side Transistors Polarity (PWM1, 3, 5 and 7 are active-high)
#pragma config T1OSCMX = ON     // Timer1 Oscillator MUX (Low-power Timer1 operation when microcontroller is in Sleep mode)

// CONFIG3H
#pragma config MCLRE = OFF      // MCLR Pin Enable bit (Disabled)

// CONFIG4L
#pragma config STVREN = ON      // Stack Full/Underflow Reset Enable bit (Stack full/underflow will cause Reset)
#pragma config LVP = ON         // Low-Voltage ICSP Enable bit (Low-voltage ICSP enabled)

// CONFIG5L
#pragma config CP0 = OFF        // Code Protection bit (Block 0 (000200-000FFFh) not code-protected)
#pragma config CP1 = OFF        // Code Protection bit (Block 1 (001000-001FFF) not code-protected)
#pragma config CP2 = OFF        // Code Protection bit (Block 2 (002000-002FFFh) not code-protected)
#pragma config CP3 = OFF        // Code Protection bit (Block 3 (003000-003FFFh) not code-protected)

// CONFIG5H
#pragma config CPB = OFF        // Boot Block Code Protection bit (Boot Block (000000-0001FFh) not code-protected)
#pragma config CPD = OFF        // Data EEPROM Code Protection bit (Data EEPROM not code-protected)

// CONFIG6L
#pragma config WRT0 = OFF       // Write Protection bit (Block 0 (000200-000FFFh) not write-protected)
#pragma config WRT1 = OFF       // Write Protection bit (Block 1 (001000-001FFF) not write-protected)
#pragma config WRT2 = OFF       // Write Protection bit (Block 2 (002000-002FFFh) not write-protected)
#pragma config WRT3 = OFF       // Write Protection bit (Block 3 (003000-003FFFh) not write-protected)

// CONFIG6H
#pragma config WRTC = OFF       // Configuration Register Write Protection bit (Configuration registers (300000-3000FFh) not write-protected)
#pragma config WRTB = OFF       // Boot Block Write Protection bit (Boot Block (000000-0001FFh) not write-protected)
#pragma config WRTD = OFF       // Data EEPROM Write Protection bit (Data EEPROM not write-protected)

// CONFIG7L
#pragma config EBTR0 = OFF      // Table Read Protection bit (Block 0 (000200-000FFFh) not protected from table reads executed in other blocks)
#pragma config EBTR1 = OFF      // Table Read Protection bit (Block 1 (001000-001FFF) not protected from table reads executed in other blocks)
#pragma config EBTR2 = OFF      // Table Read Protection bit (Block 2 (002000-002FFFh) not protected from table reads executed in other blocks)
#pragma config EBTR3 = OFF      // Table Read Protection bit (Block 3 (003000-003FFFh) not protected from table reads executed in other blocks)

// CONFIG7H
#pragma config EBTRB = OFF      // Boot Block Table Read Protection bit (Boot Block (000000-0001FFh) not protected from table reads executed in other blocks)

#define _XTAL_FREQ 25000000

This is how I connected the LCD:

When I run this code I don't get any text on the LCD. What am I doing wrong?

 

[Ian Rogers]

You haven't connected RS!!

 

[Cantafford]

You haven't connected RS!!

It's been a long day. Works now.