PORT 1

Development Boards MicroMod
1

HELLO A SMALL STUPID QUESTION!! I TRY TO ORDER a LCD 16*2 WITH LPC E2129 USING 4 PINES, P1.20 P1.21 P1.22 AND P1.23

PINES ARE OUTPUT,

HOW MUST I MAKE TO PUT a VALUE ON THESE PINES .

I TRYED IOSET |= VALUE

DOES NOT WORK

THANKS

2

Have you configured the pins as outputs?

Leon

3

YES COMPLETELY I YOU JOINT A PIECE OF CODE

#define LCD_D4 20

#define LCD_D5 21

#define LCD_D6 22

#define LCD_D7 23

#define LCD_DATA (1<<LCD_D7)|(1<<LCD_D6)|(1<<LCD_D5)|(1<<LCD_D4)

IODIR2 |=(1<<LCD_D7)|(1<<LCD_D6)|(1<<LCD_D5)|(1<<LCD_D4);

void out(unsigned char val)

{

IOCLR1 |= (LCD_DATA);

IOSET2 |= val;

}

THE SYNTHAXE IS RIGHT??

THANK YOU FOR HELP

4

SORRY

NOT IOCLR1 BUT 2

5

FULLY FUNCTION IS:

#include “lpc21xx_keil.h”

////////////////////////////////////////////definition des sorties////////////////////

#define LCD_D4 20 //p1.20

#define LCD_D5 21 //P1.21

#define LCD_D6 22 //P1.22

#define LCD_D7 23 //P1.23

#define LCD_RS 8

#define LCD_RW 10

#define LCD_EN 11

#define LCD_DATA (1<<LCD_D7)|(1<<LCD_D6)|(1<<LCD_D5)|(1<<LCD_D4)

#define LCD_COM (1<<LCD_RW)|(1<<LCD_EN)|(1<<LCD_RS)

#define lcd_rs_set() IOSET0 =(1<<LCD_RS)

#define lcd_rs_clr() IOCLR0 =(1<<LCD_RS)

#define lcd_en_set() IOSET0 =(1<<LCD_EN)

#define lcd_en_clr() IOCLR0 =(1<<LCD_EN)

#define lcd_rw_set() IOSET0 =(1<<LCD_RW)

#define lcd_rw_clr() IOCLR0 =(1<<LCD_RW)

/////////////////////////////////////////////////////////////////////////////////////////

void out(unsigned char val)

{

IOCLR1 |= (LCD_DATA);

IOSET1 |= val;

}

void write(unsigned char val)

{

out(val>>4);

out(val);

}

//////////////////////////////////////////fonctions de gestion//////////////////////////////////

void PRINT(unsigned char* str)

{

char Z;

int i;

lcd_rs_set(); //mode données

lcd_en_set(); //validation

for (i=0;i<16 ;i++)

{

Z=str*;*

  • write(Z);*

  • }*
    }
    ////////////////////////////////////////////////////////////////////////////////////////////////
    void lcd_control(unsigned char val){
    lcd_rs_clr(); //mode commande

  • lcd_en_set(); //validation*
    write(val);

  • lcd_en_clr(); //validation*
    }
    ////////////////////////////////////////////////////////////////////////////////////////////////
    lcd_init(){
    lcd_rw_clr(); //mode ecriture
    lcd_en_set(); //validation

  • lcd_control(0x28);*

  • lcd_control(0x01);//efface ecran*

  • lcd_control(0x0E); // affiche curseur*

  • lcd_control(0x14); //decale à droite*

  • lcd_en_clr() ;*

  • }*
    /////////////////////////////////////////programme principal//////////////////////////
    main(void)
    {

  • PINSEL0=0x00000000;*

  • PINSEL2=0x00000000;*
    IODIR0 |=(1<<LCD_RS)|(1<<LCD_RW)|(1<<LCD_EN);

  • IODIR1 |=(1<<LCD_D7)|(1<<LCD_D6)|(1<<LCD_D5)|(1<<LCD_D4);*

  • lcd_init();*

  • PRINT(“0123456”);*
    }
    DOESN’T WORK , THANK YOU FOR ANY HELP!!

6

I think you need to change out():

void out(unsigned char val)

{

IOCLR1 |= (LCD_DATA);

IOSET1 |= (val & 0x0F) << LCD_D4;

}

As it was, you were setting only low-numbered bits, nowhere near the actual LCD data lines.

7

hello

what the difference enter these two expressions?

lcd_ou t((val>>4)&0x0F);

lcd_out((val)&0x0F);

thanks

8

As far as I know, the most common use of IOSET and IOCLR is to use them without the OR operation (|=), because these registers already implement the OR operation implicitly.

So instead of

void out(unsigned char val)
{
IOCLR1 |= (LCD_DATA);
IOSET1 |= (val & 0x0F) << LCD_D4;
}

I think it should simply be

void out(unsigned char val)
{
IOCLR1 = (LCD_DATA);
IOSET1 = (val & 0x0F) << LCD_D4;
}

Wr.t. the other question:

lcd_out((val>>4)&0x0F) extracts the high nibble (bits 4-7) from val and sends it to lcd_out, while lcd_out((val)&0x0F) sends the low nibble (bits 0-3).

9

thank you

it is right about in/out ,

my lcd still off but ,i progress :smiley: