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please help me regarding 4 bit LCD intrfacing with atmega 32. my hardware description and code is given below:
H/W
DB7-DB4 of lcd connected to PORTD5 to PORTD2
RS in connected to PORTD7
E is connected to PORTD6
RW is connected to ground
code:
// Program to interface LCD in 4 bit mode with AVR microcontroller#define F_CPU 11059200UL#include<avr/io.h>#include<util/delay.h>#include<inttypes.h>#define en 6#define RS 7#define set_command PORTD&=~(1<<RS);#define set_data PORTD|=(1<<RS);#define set_enable PORTD|=(1<<en);#define reset_enable PORTD&=~(1<<en);void lcd_init();void lcd_init_write(unsigned char);void dis_data(unsigned char);void lcd_com(unsigned char);void lcddata(unsigned char);int main(void){unsigned char data0[11]=”aaaaa”;unsigned char data1[10]=”aaaaa”;int i=0;DDRD=0xFF;lcd_init();while(data0!=’ ’){dis_data(data0);_delay_ms(200);i++;}lcd_com(0xC5);i=0;while(data1!=’ ’){dis_data(data1);_delay_ms(200);i++;}while(1);}void lcd_init() // fuction for intialize{_delay_ms(40); ;lcd_init_write(0x30); //Special Sequence:Write Function Set._delay_us(4100);lcd_init_write(0x30); //Special Sequence:Write Function Set._delay_us(100);lcd_init_write(0x30); //Special Sequence:Write Function Set._delay_us(40);lcd_init_write(0x20); // 0x20 for 4-bit_delay_us(40);lcd_com(0x28); //Display Off, Cursor Off, Blink Off_delay_us(40);lcd_com(0x08); // Clear Screen & Returns the Cursor Home_delay_us(40);lcd_com(0x01);_delay_us(1600);lcd_com(0x06); //Inc cursor to the right when writing and don’t shift screen_delay_us(40);lcd_com(0x0c);_delay_us(40);}void lcd_init_write(unsigned char a){set_command; //RS=0;PORTD=(a>>2); //DB7-DB4 connected to PORTD5-PORTD2set_enable; //E=1;_delay_ms(10); //(lcd_delay);reset_enable;//E=0;_delay_us(40);}void lcd_com(unsigned char a){unsigned char temp;set_command; //RS=0;temp=a;temp&=0xf0;temp=(temp>>2); // Mask Lower 4 BitsPORTD&=0xc3;// Make No Affect on 0ther Port PinsPORTD|=temp; // Send Higher Nibble to LCDPORTset_enable;//E=1;_delay_ms(10); //Send Enable Signal to LCDreset_enable;//E=0;temp=a<<4; //Left Shift Byte Four Timestemp&=0xf0; // Mask Higher 4 Bitstemp=(temp>>2); // Mask Lower 4 BitsPORTD&=0xc3; // Make No Affect on 0ther Port PinsPORTD|=temp; // Send Lower Nibble to LCDPORTset_enable;//E=1;_delay_ms(10); // Send Enable Signal to LCDreset_enable;//E=0;_delay_us(40);}void dis_data(unsigned char data_value){unsigned char data_value1;data_value1=data_value;data_value1 &=0xF0;data_value1=(data_value1>>2);lcddata(data_value1);data_value1=((data_value<<4)&0xF0);data_value1=(data_value1>>2);lcddata(data_value1);}void lcddata(unsigned char dataout){set_data;PORTD=dataout;set_enable;_delay_ms(1);reset_enable;}you just reffer \extremeelectronics.co.in\ and read the AVR lcd interfaceing tutorial. you may download
the lcd.c , lcd.h, and myutils.h file and add source and header file to your main program and then you can easily use lcd as per your requirement.
But remember if you are going to use this source file keep one thing in mind you have to connect the datalines of lcd DB4-DB7 with 0-3 no. pins of any port. you have to use the first 4 bits of any portof mcu
k..
can any one send me code for display characters on lcd interfacing with atmega 32. i am beginner so i am finding many problems . i am using code vision avr c compiler. my email id is [email protected]
Dear Friend,
Posting a working code is not the solution. You need proper & working hardware & details of LCD port connections e.t.c. Share you connection decription so that one can understand where exactly you connected the LCD & other connections. This will help you out with expected result.
Hi Anjum,
Without knowing what issue are you facing with the project, how can someone help you with it?
i wana display msg on lcd interfaced with atmega 32. i want to use PB.0-rs, PB.1-rw, PB.2- en , and want to use data pins of same port i.e PB.4 TO PB.7. Here is my code…..cn ny 1 help me to solv out the prblm. wn i burn this code nthing is display on lcd.
//Program to Display string on LCD using AVR Microcontroller (ATmega16)/*LCD DATA port—-PORT Bsignal port
PORT Drs
PD0rw
PD1en
PD2*/#include<mega32.h>#include<delay.h>#define LCD_DATA PORTB //LCD data port#define ctrl PORTB#define en PORTB2 // enable signal#define rw PORTB1 // read/write signal#define rs PORTB0 // register select signalvoid LCD_cmd(unsigned char cmd);void init_LCD(void);void LCD_write(unsigned char data);void LCD_write_string(unsigned char *str) ;void main(){DDRB=0xff;PORTB=0xf0;init_LCD(); // initialization of LCDdelay_ms(50); // delay of 50 mili secondsLCD_write_string(“sushilprajapati”); // function to print string on LCD}void init_LCD(void){LCD_cmd(0x38); // initialization of 16X2 LCD in 8bit modedelay_ms(1);LCD_cmd(0x01); // clear LCDdelay_ms(1);LCD_cmd(0x0E); // cursor ONdelay_ms(1);LCD_cmd(0x80); // —8 go to first line and –0 is for 0th positiondelay_ms(1);return;}void LCD_cmd(unsigned char cmd){LCD_DATA=cmd;ctrl =(0<<rs)|(0<<rw)|(1<<en);delay_ms(1);ctrl =(0<<rs)|(0<<rw)|(0<<en);delay_ms(50);return;}void LCD_write(unsigned char data){LCD_DATA= data;ctrl = (1<<rs)|(0<<rw)|(1<<en);delay_ms(1);ctrl = (1<<rs)|(0<<rw)|(0<<en);delay_ms(50);return ;}void LCD_write_string(unsigned char *str) //store address value of the string in pointer *str{int i=0;while(str!=’ ’) // loop will go on till the NULL character in the string{LCD_write(str); // sending data on LCD byte by bytei++;}return;}Hi,
If everything else is properly coded, then I can see the same thing with which I’ve struggled a lot few years back. And here is my workaround.
Just change the parameter of the function LCD_write_string to const char *str, in both decleration and defenition, like the following
void LCD_write_string(const char *str)
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