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lcd project at stm32

Hi, I'm new in embedded system,I've stm32f100rb and I want to display a string at an lcd named jhd162a 16x2, but when I test it, the lcd always display a black line,I test it with an empty board and it's the same problem, one black line.
anyone have an idea please???
and thank you.

Parents

0 Sahsinho Houssem over 11 years ago

I set the GPIO_Speed to 50 Mhz and it the same problem :/
this is all of the code project:

lcd_hd44780.h:

//******************************************************************************
//    THE SOFTWARE INCLUDED IN THIS FILE IS FOR GUIDANCE ONLY.
//    AUTHOR SHALL NOT BE HELD LIABLE FOR ANY DIRECT, INDIRECT
//    OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
//    FROM USE OF THIS SOFTWARE.
//******************************************************************************

//##############################################################################
// lcd_hd44780.h
//##############################################################################

//****************************************************************************//
#include "STM32vldiscovery.h"


#define LCD_GPIO GPIOB
#define LCD_CLK_LINE RCC_APB2Periph_GPIOB

#define LCD_D4 GPIO_Pin_6
#define LCD_D5 GPIO_Pin_5
#define LCD_D6 GPIO_Pin_4
#define LCD_D7 GPIO_Pin_3

#define LCD_RS GPIO_Pin_9
#define LCD_RW GPIO_Pin_8
#define LCD_EN GPIO_Pin_7
//******************************************************************************//


#define HD44780_CLEAR                                          0x01

#define HD44780_HOME                                           0x02

#define HD44780_ENTRY_MODE                                 0x04
        #define HD44780_EM_SHIFT_CURSOR          0
        #define HD44780_EM_SHIFT_DISPLAY         1
        #define HD44780_EM_DECREMENT               0
        #define HD44780_EM_INCREMENT               2

#define HD44780_DISPLAY_ONOFF                      0x08
        #define HD44780_DISPLAY_OFF                  0
        #define HD44780_DISPLAY_ON                         4
        #define HD44780_CURSOR_OFF                         0
        #define HD44780_CURSOR_ON                            2
        #define HD44780_CURSOR_NOBLINK     0
        #define HD44780_CURSOR_BLINK               1

#define HD44780_DISPLAY_CURSOR_SHIFT 0x10
        #define HD44780_SHIFT_CURSOR               0
        #define HD44780_SHIFT_DISPLAY              8
        #define HD44780_SHIFT_LEFT                         0
        #define HD44780_SHIFT_RIGHT                  4

#define HD44780_FUNCTION_SET                       0x20
        #define HD44780_FONT5x7                              0
        #define HD44780_FONT5x10                             4
        #define HD44780_ONE_LINE                             0
        #define HD44780_TWO_LINE                             8
        #define HD44780_4_BIT                                  0
        #define HD44780_8_BIT                                  16

#define HD44780_CGRAM_SET                                    0x40

#define HD44780_DDRAM_SET                                    0x80

//##############################################################
void lcd_init(void);
void lcd_cls(void);
void lcd_str(unsigned char * text);
void lcd_strxy(unsigned char * text, unsigned char x, unsigned char y);
void lcd_locate(unsigned char x, unsigned char y);
void lcd_int(int n);
void lcd_intxy(int n, unsigned char x, unsigned char y);

//###############################################################

void lcd_writedata(unsigned char dataToWrite);
void lcd_writecommand(unsigned char commandToWrite);
void lcd_writebinary(unsigned int var, unsigned char bitCount);
void lcd_addchar (unsigned char chrNum, unsigned char n, const unsigned char *p);

Reply

0 Sahsinho Houssem over 11 years ago

I set the GPIO_Speed to 50 Mhz and it the same problem :/
this is all of the code project:

lcd_hd44780.h:

//******************************************************************************
//    THE SOFTWARE INCLUDED IN THIS FILE IS FOR GUIDANCE ONLY.
//    AUTHOR SHALL NOT BE HELD LIABLE FOR ANY DIRECT, INDIRECT
//    OR CONSEQUENTIAL DAMAGES WITH RESPECT TO ANY CLAIMS ARISING
//    FROM USE OF THIS SOFTWARE.
//******************************************************************************

//##############################################################################
// lcd_hd44780.h
//##############################################################################

//****************************************************************************//
#include "STM32vldiscovery.h"


#define LCD_GPIO GPIOB
#define LCD_CLK_LINE RCC_APB2Periph_GPIOB

#define LCD_D4 GPIO_Pin_6
#define LCD_D5 GPIO_Pin_5
#define LCD_D6 GPIO_Pin_4
#define LCD_D7 GPIO_Pin_3

#define LCD_RS GPIO_Pin_9
#define LCD_RW GPIO_Pin_8
#define LCD_EN GPIO_Pin_7
//******************************************************************************//


#define HD44780_CLEAR                                          0x01

#define HD44780_HOME                                           0x02

#define HD44780_ENTRY_MODE                                 0x04
        #define HD44780_EM_SHIFT_CURSOR          0
        #define HD44780_EM_SHIFT_DISPLAY         1
        #define HD44780_EM_DECREMENT               0
        #define HD44780_EM_INCREMENT               2

#define HD44780_DISPLAY_ONOFF                      0x08
        #define HD44780_DISPLAY_OFF                  0
        #define HD44780_DISPLAY_ON                         4
        #define HD44780_CURSOR_OFF                         0
        #define HD44780_CURSOR_ON                            2
        #define HD44780_CURSOR_NOBLINK     0
        #define HD44780_CURSOR_BLINK               1

#define HD44780_DISPLAY_CURSOR_SHIFT 0x10
        #define HD44780_SHIFT_CURSOR               0
        #define HD44780_SHIFT_DISPLAY              8
        #define HD44780_SHIFT_LEFT                         0
        #define HD44780_SHIFT_RIGHT                  4

#define HD44780_FUNCTION_SET                       0x20
        #define HD44780_FONT5x7                              0
        #define HD44780_FONT5x10                             4
        #define HD44780_ONE_LINE                             0
        #define HD44780_TWO_LINE                             8
        #define HD44780_4_BIT                                  0
        #define HD44780_8_BIT                                  16

#define HD44780_CGRAM_SET                                    0x40

#define HD44780_DDRAM_SET                                    0x80

//##############################################################
void lcd_init(void);
void lcd_cls(void);
void lcd_str(unsigned char * text);
void lcd_strxy(unsigned char * text, unsigned char x, unsigned char y);
void lcd_locate(unsigned char x, unsigned char y);
void lcd_int(int n);
void lcd_intxy(int n, unsigned char x, unsigned char y);

//###############################################################

void lcd_writedata(unsigned char dataToWrite);
void lcd_writecommand(unsigned char commandToWrite);
void lcd_writebinary(unsigned int var, unsigned char bitCount);
void lcd_addchar (unsigned char chrNum, unsigned char n, const unsigned char *p);

Children

0 Sahsinho Houssem over 11 years ago in reply to Sahsinho Houssem

lcd_hd44780.c:


#include "lcd_hd44780_lib.h"
#include "stm32f10x_gpio.h"
#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "STM32vldiscovery.h"

GPIO_InitTypeDef GPIO_InitStructure;

//-----------------------------------------------------------------------------
void lcd_writenibble(unsigned char nibbleToWrite)
{
  GPIO_WriteBit(LCD_GPIO, LCD_EN, Bit_SET);
  GPIO_WriteBit(LCD_GPIO, LCD_D4,(BitAction) (nibbleToWrite & 0x01));
  GPIO_WriteBit(LCD_GPIO, LCD_D5,(BitAction)(nibbleToWrite & 0x02));
  GPIO_WriteBit(LCD_GPIO, LCD_D6,(BitAction)(nibbleToWrite & 0x04));
  GPIO_WriteBit(LCD_GPIO, LCD_D7,(BitAction)(nibbleToWrite & 0x08));
  GPIO_WriteBit(LCD_GPIO, LCD_EN, Bit_RESET);
}


//-----------------------------------------------------------------------------
unsigned char LCD_ReadNibble(void)
{
  unsigned char tmp = 0;
  GPIO_WriteBit(LCD_GPIO, LCD_EN, Bit_SET);
  tmp |= (GPIO_ReadInputDataBit(LCD_GPIO, LCD_D4) << 0);
  tmp |= (GPIO_ReadInputDataBit(LCD_GPIO, LCD_D5) << 1);
  tmp |= (GPIO_ReadInputDataBit(LCD_GPIO, LCD_D6) << 2);
  tmp |= (GPIO_ReadInputDataBit(LCD_GPIO, LCD_D7) << 3);
  GPIO_WriteBit(LCD_GPIO, LCD_EN, Bit_RESET);
  return tmp;
}


//-----------------------------------------------------------------------------
unsigned char LCD_ReadStatus(void)
{
  unsigned char status = 0;

    GPIO_InitStructure.GPIO_Pin   =  LCD_D4 | LCD_D5 | LCD_D6 | LCD_D7;
    GPIO_InitStructure.GPIO_Mode  =  GPIO_Mode_IPD;
    GPIO_Init(LCD_GPIO, &GPIO_InitStructure);

    GPIO_WriteBit(LCD_GPIO, LCD_RW, Bit_SET);
    GPIO_WriteBit(LCD_GPIO, LCD_RS, Bit_RESET);

    status |= (LCD_ReadNibble() << 4);
    status |= LCD_ReadNibble();

    GPIO_InitStructure.GPIO_Pin   =  LCD_D4 | LCD_D5 | LCD_D6 | LCD_D7;
    GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;
    GPIO_Init(LCD_GPIO, &GPIO_InitStructure);

  return status;
}


//-----------------------------------------------------------------------------
void lcd_writedata(unsigned char dataToWrite)
{
  GPIO_WriteBit(LCD_GPIO, LCD_RW, Bit_RESET);
  GPIO_WriteBit(LCD_GPIO, LCD_RS, Bit_SET);

  lcd_writenibble(dataToWrite >> 4);
  lcd_writenibble(dataToWrite & 0x0F);

  while(LCD_ReadStatus() & 0x80);
}


//-----------------------------------------------------------------------------
void lcd_writecommand(unsigned char commandToWrite)
{
  GPIO_WriteBit(LCD_GPIO, LCD_RW | LCD_RS, Bit_RESET);
  lcd_writenibble(commandToWrite >> 4);
  lcd_writenibble(commandToWrite & 0x0F);

  while(LCD_ReadStatus() & 0x80);
}


//-----------------------------------------------------------------------------
void lcd_str(unsigned char * text)
{
  while(*text)
    lcd_writedata(*text++);
}


//-----------------------------------------------------------------------------
void lcd_locate(unsigned char x, unsigned char y)
{
  lcd_writecommand(HD44780_DDRAM_SET | (x + (0x40 * y)));
}


//-----------------------------------------------------------------------------
void lcd_strxy(unsigned char * text, unsigned char x, unsigned char y)
{
  lcd_locate(x,y);
  while(*text)
    lcd_writedata(*text++);
}


//-----------------------------------------------------------------------------
void lcd_writebinary(unsigned int var, unsigned char bitCount)
{
  signed char i;

  for(i = (bitCount - 1); i >= 0; i--)
     {
     lcd_writedata((var & (1 << i))?'1':'0');
     }
}


//-----------------------------------------------------------------------------
void LCD_ShiftLeft(void)
{
  lcd_writecommand(HD44780_DISPLAY_CURSOR_SHIFT | HD44780_SHIFT_LEFT | HD44780_SHIFT_DISPLAY);
}


//-----------------------------------------------------------------------------
void LCD_ShiftRight(void)
{
  lcd_writecommand(HD44780_DISPLAY_CURSOR_SHIFT | HD44780_SHIFT_RIGHT | HD44780_SHIFT_DISPLAY);
}


//-----------------------------------------------------------------------------
void lcd_init(void)
{
  volatile unsigned char i = 0;
  volatile unsigned int delayCnt = 0;
        RCC_APB2PeriphClockCmd(LCD_CLK_LINE, ENABLE);
  GPIO_InitStructure.GPIO_Pin = LCD_D4|LCD_D5|LCD_D6|LCD_D7|LCD_RS|LCD_RW|LCD_EN;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_Out_PP;

  GPIO_Init(LCD_GPIO, &GPIO_InitStructure);

  GPIO_ResetBits(LCD_GPIO, LCD_RS | LCD_EN | LCD_RW);

  for(delayCnt = 0; delayCnt < 300000; delayCnt++);

  for(i = 0; i < 3; i++) {
    lcd_writenibble(0x03);
    for(delayCnt = 0; delayCnt < 30000; delayCnt++);
  }

  lcd_writenibble(0x02);

  for(delayCnt = 0; delayCnt < 6000; delayCnt++);

  lcd_writecommand(HD44780_FUNCTION_SET |
                   HD44780_FONT5x7 |
                   HD44780_TWO_LINE |
                   HD44780_4_BIT);

  lcd_writecommand(HD44780_DISPLAY_ONOFF |
                   HD44780_DISPLAY_OFF);

  lcd_writecommand(HD44780_CLEAR);

  lcd_writecommand(HD44780_ENTRY_MODE |
                   HD44780_EM_SHIFT_CURSOR |
                   HD44780_EM_INCREMENT);

  lcd_writecommand(HD44780_DISPLAY_ONOFF |
                   HD44780_DISPLAY_ON |
                   HD44780_CURSOR_OFF |
                   HD44780_CURSOR_NOBLINK);

}


//-----------------------------------------------------------------------------
void lcd_addchar (unsigned char chrNum, unsigned char n, const unsigned char *p)
{
        lcd_writecommand(HD44780_CGRAM_SET | chrNum * 8);
        n *= 8;
        do
                lcd_writedata(*p++);
        while (--n);
}


//-----------------------------------------------------------------------------
void lcd_cls(void){
        lcd_writecommand(HD44780_CLEAR);
}



unsigned char* intToStr(int n)
        {
     int i = 0;
     char *tmp = (char*)malloc(sizeof(char));
     unsigned char *ret = (unsigned char*)malloc(12);
     if(n < 0) {
          *ret = '-';
          i++;
          n = -n;
     }
     do {
          *tmp = n % 10 + 48;
          n -= n % 10;
          if(n > 9) *tmp++;
     }
     while(n /= 10);
     while(ret[i++] = *tmp--);
     return ret;
}

void lcd_int(int n){

        lcd_str(intToStr(n));
}

void lcd_intxy(int n, unsigned char x, unsigned char y){
        lcd_locate(x,y);
        lcd_str(intToStr(n));
}

0 Sahsinho Houssem over 11 years ago in reply to Sahsinho Houssem

main.c

#include <stddef.h>
#include "stm32f10x_rcc.h"
#include "stm32f10x_gpio.h"
#include "lcd_hd44780_lib.h"
#include "STM32vldiscovery.h"

int main(void)
{

        RCC_PLLConfig (0x00010000, RCC_PLLMul_2);
        lcd_init();



          while (1)
          {

                  lcd_locate(1,0);
                  lcd_str("ENSI");
                  lcd_locate(7,0);
                  lcd_str("STM32F1");
                  lcd_locate(0,1);
                  lcd_str("electronics");

          }

}

0 Andy Neil over 11 years ago in reply to Sahsinho Houssem

"I set the GPIO_Speed to 50 Mhz and it the same problem"

That has nothing to do with busy loops!

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0 Sahsinho Houssem over 11 years ago in reply to Andy Neil

sorry, but I can't understand what I have to do ??
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