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huichoman
Joined: 20 Nov 2006
Posts: 2
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| LCD 40x4 driver |
 Posted: Sun Sep 16, 2007 3:48 pm |
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This driver is for use with 40x4 LCDs. It's based in flex_lcd420 by PCM programmer.
Proteus simulation.
driver source code
| Code: |
//lcd_40x4_h.c by huichoman
//Modificación flex_LCD420.c
//JOSE LUIS SANTIAGO MORALES --Huichoman--
//Tuxtla Gutiérrez, Chiapas, México
// These pins are for my Microchip PicDem2-Plus board,
// which I used to test this driver.
// An external 20x4 LCD is connected to these pins.
// Change these pins to match your own board's connections.
#define LCD_DB4 PIN_B4
#define LCD_DB5 PIN_B5
#define LCD_DB6 PIN_B6
#define LCD_DB7 PIN_B7
#define LCD_RS PIN_B0
#define LCD_RW PIN_B1
#define LCD_E1 PIN_B2
#define LCD_E2 PIN_B3
/*
// To prove that the driver can be used with random
// pins, I also tested it with these pins:
#define LCD_DB4 PIN_D4
#define LCD_DB5 PIN_B1
#define LCD_DB6 PIN_C5
#define LCD_DB7 PIN_B5
#define LCD_RS PIN_E2
#define LCD_RW PIN_B2
#define LCD_E1 PIN_D6
*/
// If you want only a 6-pin interface to your LCD, then
// connect the R/W pin on the LCD to ground, and comment
// out the following line. Doing so will save one PIC
// pin, but at the cost of losing the ability to read from
// the LCD. It also makes the write time a little longer
// because a static delay must be used, instead of polling
// the LCD's busy bit. Normally a 6-pin interface is only
// used if you are running out of PIC pins, and you need
// to use as few as possible for the LCD.
#define USE_RW_PIN 1
// These are the line addresses for most 4x20 LCDs.
#define LCD_LINE_1_ADDRESS 0x00
#define LCD_LINE_2_ADDRESS 0x40
#define LCD_LINE_3_ADDRESS 0x00
#define LCD_LINE_4_ADDRESS 0x40
// These are the line addresses for LCD's which use
// the Hitachi HD66712U controller chip.
/*
#define LCD_LINE_1_ADDRESS 0x00
#define LCD_LINE_2_ADDRESS 0x20
#define LCD_LINE_3_ADDRESS 0x40
#define LCD_LINE_4_ADDRESS 0x60
*/
//========================================
#define lcd_type 2 // 0=5x7, 1=5x10, 2=2 lines(or more)
int8 lcd_line;
int8 const LCD_INIT_STRING[4] =
{
0x20 | (lcd_type << 2), // Set mode: 4-bit, 2+ lines, 5x8 dots
0xc, // Display on
1, // Clear display
6 // Increment cursor
};
//DISPLAY 1
//-------------------------------------
void lcd_send_nibble1(int8 nibble)
{
// Note: !! converts an integer expression
// to a boolean (1 or 0).
output_bit(LCD_DB4, !!(nibble & 1));
output_bit(LCD_DB5, !!(nibble & 2));
output_bit(LCD_DB6, !!(nibble & 4));
output_bit(LCD_DB7, !!(nibble & 8));
delay_cycles(1);
output_high(LCD_E1);
delay_us(2);
output_low(LCD_E1);
}
//DISPLAY 2
//-------------------------------------
void lcd_send_nibble2(int8 nibble)
{
// Note: !! converts an integer expression
// to a boolean (1 or 0).
output_bit(LCD_DB4, !!(nibble & 1));
output_bit(LCD_DB5, !!(nibble & 2));
output_bit(LCD_DB6, !!(nibble & 4));
output_bit(LCD_DB7, !!(nibble & 8));
delay_cycles(1);
output_high(LCD_E2);
delay_us(2);
output_low(LCD_E2);
}
//-----------------------------------
// This sub-routine is only called by lcd_read_byte().
// It's not a stand-alone routine. For example, the
// R/W signal is set high by lcd_read_byte() before
// this routine is called.
#ifdef USE_RW_PIN
int8 lcd_read_nibble(void)
{
int8 retval;
// Create bit variables so that we can easily set
// individual bits in the retval variable.
#bit retval_0 = retval.0
#bit retval_1 = retval.1
#bit retval_2 = retval.2
#bit retval_3 = retval.3
retval = 0;
output_high(LCD_E1);
delay_us(1);
retval_0 = input(LCD_DB4);
retval_1 = input(LCD_DB5);
retval_2 = input(LCD_DB6);
retval_3 = input(LCD_DB7);
output_low(LCD_E1);
delay_us(1);
return(retval);
}
#endif
//---------------------------------------
// Read a byte from the LCD and return it.
#ifdef USE_RW_PIN
int8 lcd_read_byte(void)
{
int8 low;
int8 high;
output_high(LCD_RW);
delay_cycles(1);
high = lcd_read_nibble();
low = lcd_read_nibble();
return( (high<<4) | low);
}
#endif
//DISPLAY 1
//----------------------------------------
// Send a byte to the LCD.
void lcd_send_byte1(int8 address, int8 n)
{
output_low(LCD_RS);
#ifdef USE_RW_PIN
while(bit_test(lcd_read_byte(),7)) ;
#else
delay_us(60);
#endif
if(address)
output_high(LCD_RS);
else
output_low(LCD_RS);
delay_cycles(1);
#ifdef USE_RW_PIN
output_low(LCD_RW);
delay_cycles(1);
#endif
output_low(LCD_E1);
lcd_send_nibble1(n >> 4);
lcd_send_nibble1(n & 0xf);
}
//----------------------------
//DISPLAY 2
//----------------------------------------
// Send a byte to the LCD.
void lcd_send_byte2(int8 address, int8 n)
{
output_low(LCD_RS);
#ifdef USE_RW_PIN
while(bit_test(lcd_read_byte(),7)) ;
#else
delay_us(60);
#endif
if(address)
output_high(LCD_RS);
else
output_low(LCD_RS);
delay_cycles(1);
#ifdef USE_RW_PIN
output_low(LCD_RW);
delay_cycles(1);
#endif
output_low(LCD_E2);
lcd_send_nibble2(n >> 4);
lcd_send_nibble2(n & 0xf);
}
//----------------------------
//DISPLAY 1
//----------------------------
void lcd_init1(void)
{
int8 i;
lcd_line = 1;
output_low(LCD_RS);
#ifdef USE_RW_PIN
output_low(LCD_RW);
#endif
output_low(LCD_E1);
// Some LCDs require 15 ms minimum delay after
// power-up. Others require 30 ms. I'm going
// to set it to 35 ms, so it should work with
// all of them.
delay_ms(35);
for(i=0 ;i < 3; i++)
{
lcd_send_nibble1(0x03);
delay_ms(5);
}
lcd_send_nibble1(0x02);
for(i=0; i < sizeof(LCD_INIT_STRING); i++)
{
lcd_send_byte1(0, LCD_INIT_STRING[i]);
// If the R/W signal is not used, then
// the busy bit can't be polled. One of
// the init commands takes longer than
// the hard-coded delay of 50 us, so in
// that case, lets just do a 5 ms delay
// after all four of them.
#ifndef USE_RW_PIN
delay_ms(5);
#endif
}
}
//----------------------------
//DISPLAY 2
//----------------------------
void lcd_init2(void)
{
int8 i;
lcd_line = 1;
output_low(LCD_RS);
#ifdef USE_RW_PIN
output_low(LCD_RW);
#endif
output_low(LCD_E2);
// Some LCDs require 15 ms minimum delay after
// power-up. Others require 30 ms. I'm going
// to set it to 35 ms, so it should work with
// all of them.
delay_ms(35);
for(i=0 ;i < 3; i++)
{
lcd_send_nibble2(0x03);
delay_ms(5);
}
lcd_send_nibble2(0x02);
for(i=0; i < sizeof(LCD_INIT_STRING); i++)
{
lcd_send_byte2(0, LCD_INIT_STRING[i]);
// If the R/W signal is not used, then
// the busy bit can't be polled. One of
// the init commands takes longer than
// the hard-coded delay of 50 us, so in
// that case, lets just do a 5 ms delay
// after all four of them.
#ifndef USE_RW_PIN
delay_ms(5);
#endif
}
}
//----------------------------
void lcd_gotoxy(int8 x, int8 y)
{
int8 address;
switch(y)
{
case 1:
address = LCD_LINE_1_ADDRESS;
break;
case 2:
address = LCD_LINE_2_ADDRESS;
break;
case 3:
address = LCD_LINE_3_ADDRESS;
break;
case 4:
address = LCD_LINE_4_ADDRESS;
break;
default:
address = LCD_LINE_1_ADDRESS;
break;
}
address += x-1;
lcd_send_byte1(0, 0x80 | address);
lcd_send_byte2(0, 0x80 | address);
}
// DISPLAY 1
//-----------------------------
void lcd_putc1(char c)
{
switch(c)
{
case '\f':
lcd_send_byte1(0,1);
lcd_line = 1;
delay_ms(2);
break;
case '\n':
lcd_gotoxy(1, ++lcd_line);
break;
case '\b':
lcd_send_byte1(0,0x10);
break;
default:
lcd_send_byte1(1,c);
break;
}
}
//------------------------------
//DISPLAY 2
//-----------------------------
void lcd_putc2(char c)
{
switch(c)
{
case '\f':
lcd_send_byte2(0,1);
lcd_line = 1;
delay_ms(2);
break;
case '\n':
lcd_gotoxy(1, ++lcd_line);
break;
case '\b':
lcd_send_byte2(0,0x10);
break;
default:
lcd_send_byte2(1,c);
break;
}
}
//------------------------------
#ifdef USE_RW_PIN
char lcd_getc(int8 x, int8 y)
{
char value;
lcd_gotoxy(x,y);
// Wait until busy flag is low.
while(bit_test(lcd_read_byte(),7));
output_high(LCD_RS);
value = lcd_read_byte();
output_low(LCD_RS);
return(value);
}
#endif
|
Test program source code
| Code: |
//lcd_40x4.c
//Test rutina lcd_40x4_h.c
//Huichoman
#include <18F2525.h>
#use delay(clock=4000000)
#fuses XT, NOPROTECT, PUT, NOWDT, NOBROWNOUT, NOLVP, NOCPD, NOWRT
#include <lcd_40x4_h.c>
void main() {
lcd_init1();
delay_ms(2);
lcd_init2();
while(true) {
//TEST 1
//---------------------------------
lcd_gotoxy(1,1);
printf(lcd_putc1,"JOSE LUIS SANTIAGO MORALES");
delay_ms(1500);
lcd_gotoxy(1,2);
printf(lcd_putc1,"HUICHOMAN");
delay_ms(1500);
lcd_gotoxy(1,1);
printf(lcd_putc2,"TEST LCD 40X4");
delay_ms(1500);
lcd_gotoxy(1,2);
printf(lcd_putc2,"PRUEBA SUPERADA");
delay_ms(1000);
lcd_putc1("\f");
delay_ms(1500);
lcd_putc2("\f");
delay_ms(1500);
//---------------------------------
//TEST 1
//---------------------------------
lcd_gotoxy(1,1);
printf(lcd_putc1,"LINEA 1 LCD1");
delay_ms(1500);
lcd_gotoxy(1,2);
printf(lcd_putc1,"LINEA 2 LCD1");
delay_ms(1500);
lcd_gotoxy(1,1);
printf(lcd_putc2,"LINEA 1 LCD2");
delay_ms(1500);
lcd_gotoxy(1,2);
printf(lcd_putc2,"LINEA 2 LCD2");
delay_ms(1500);
lcd_gotoxy(1,1);
printf(lcd_putc1,"LCD 1 LINEA 1");
delay_ms(1500);
lcd_gotoxy(1,1);
printf(lcd_putc2,"LCD 2 LINEA 1");
delay_ms(1500);
lcd_gotoxy(1,2);
printf(lcd_putc1,"LCD 1 LINEA 2");
delay_ms(1500);
lcd_gotoxy(1,2);
printf(lcd_putc2,"LCD 2 LINEA 2");
delay_ms(1500);
lcd_putc1("\f");
delay_ms(1500);
lcd_putc2("\f");
//---------------------------------
}
}
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MCDOGANAY
Joined: 09 Apr 2009
Posts: 3
Location: turkey
|
| LCD 40X4 LINE3 & LINE4 ERROR |
| Posted: Fri Apr 10, 2009 6:37 am |
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| this driver, line3 and line4 not cursor home. Why ? |
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khalid_mehmood_attock
Joined: 13 Apr 2010
Posts: 1
|
| Code 40x4 LCD CODE |
| Posted: Tue Apr 13, 2010 1:27 am |
|
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First Correct these lines
| Code: |
//TEST 1
//---------------------------------
lcd_gotoxy(1,1);
printf(lcd_putc1,"LINEA 1 LCD1");
delay_ms(1500);
lcd_gotoxy(1,2);
printf(lcd_putc1,"LINEA 2 LCD1");
delay_ms(1500);
lcd_gotoxy(1,3);
printf(lcd_putc2,"LINEA 1 LCD2");
delay_ms(1500);
lcd_gotoxy(1,4);
printf(lcd_putc2,"LINEA 2 LCD2");
delay_ms(1500);
//-------------------------
|
and Change the LCD Module in Proteus
LC4857
It works properly. |
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