trying to interface lcd screen

[mle]

Hello,
I am trying to write a program to test a 2x24 lcd screen using a pic 16f877. The pin connections are as follows:

// A1 enable
// A3 rs
// Gnd rw
// D0 D4
// D1 D5
// D2 D6
// D3 D7

When I run the program, I get a bunch of garbage on the screen.

This is the entire program

// As defined in the following structure the pin connection is as follows:
// A1 enable
// A3 rs
// Gnd rw
// D0 D4
// D1 D5
// D2 D6
// D3 D7
//
// LCD pins D0-D3 ,r/w are not used and PIC B3 is not used.

#include <16F877.h>
#use delay(clock = 4000000)

#BIT LCD_EN = 0x05.1 //maps the enable bit to RA1
#BIT LCD_RS = 0x05.3 //maps the rs bit to RA3
#BYTE PORTA = 0x05 //PORTA IS ADDRESS 5
#BYTE PORTD = 0x08 //PORTD IS ADDRESS 8

#define LCD_STROBE ((LCD_EN = 1),(LCD_EN=0))

/* write a byte to the LCD in 4 bit mode */

void lcd_write(char c)
{
PORTD = (PORTD & 0xF0) | (c >> 4);
LCD_STROBE;
PORTD = (PORTD & 0xF0) | (c & 0x0F);
LCD_STROBE;
delay_us(40);
}


// Clear and home the LCD

void lcd_clear(void)
{
LCD_RS = 0;
lcd_write(0x1);
delay_ms(2);
}

/* write a string of chars to the LCD */

void lcd_puts(char * s)
{
LCD_RS = 1; // write characters
while(*s)
lcd_write(*s++);
}

void lcd_putch(char c)
{
LCD_RS = 1; // write characters
PORTD = (PORTD & 0xF0) | (c >> 4);
LCD_STROBE;
PORTD = (PORTD & 0xF0) | (c & 0x0F);
LCD_STROBE;
delay_us(40);
}


/* Go to the specified position*/

void lcd_goto(char pos)
{
LCD_RS = 0;
lcd_write(0x80+pos);
}

/* initialize the LCD - put into 4 bit mode */

void lcd_init(void)
{
LCD_RS = 0; // write control bytes
delay_ms(15); // power on delay
PORTD = (PORTD & 0xF0) | (0x03); //ATTENTION
LCD_STROBE;
delay_ms(5);
LCD_STROBE;
delay_us(100);
LCD_STROBE;
delay_ms(5);
PORTD = (PORTD & 0xF0) | (0x20); // set 4 bit mode
LCD_STROBE;
delay_us(40);
lcd_write(0x28); // 4 bit mode, 1/16 duty, 5x8 font
lcd_write(0x08); // display off
lcd_write(0x0F); // display on, blink curson on
lcd_write(0x06); // entry mode
}

void main(){
/*----------configure all the ports-------*/
Set_Tris_A(0x00); //set port A to outputs
Set_Tris_B(0x33); //make RB5, RB4(BUTTONS),
//RB1 (DQin) and RB0(pulse in) inputs
Set_Tris_C(0xD7); //RC7, RC6 (for Hserin/Hserout), RC4(RTC),
//RC2, RC1, RC0 inputs
Set_Tris_D(0x00); //set port D to outputs
Set_Tris_E(0x00); //set port E to outputs

delay_us(500);
lcd_init();

lcd_clear();
lcd_puts("Hello World");


while(1);
}

Thanks for the help,
mle
___________________________
This message was ported from CCS's old forum
Original Post ID: 144515534

[mle]

Forget it, it works!!
___________________________
This message was ported from CCS's old forum
Original Post ID: 144515535