Welcome to EDAboard.com

Welcome to our site! EDAboard.com is an international Electronics Discussion Forum focused on EDA software, circuits, schematics, books, theory, papers, asic, pld, 8051, DSP, Network, RF, Analog Design, PCB, Service Manuals... and a whole lot more! To participate you need to register. Registration is free. Click here to register now.

[SOLVED] problem with my 16x2 LCD

Status
Not open for further replies.

Dilpreet Singh

Junior Member level 1
Joined
Jan 21, 2015
Messages
19
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
155
i write a code for jhd-16 * 2 lcd it is working on protious but not on hardware ?
i give about 50 ms delay after each command even it is not working with such a big delay
 

Dilpreet Singh

Junior Member level 1
Joined
Jan 21, 2015
Messages
19
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
155

Code C - [expand]
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
#include <avr/io.h>
#include <avr/delay.h>
#include <util/delay.h>
 
#define RS 0
#define RW 1
#define EN 2
#define lcd_port PORTD
 
#define F_CPU 11592000ul
 
 
 
#define sbit(reg,bit)   reg |= (1<<bit)
#define cbit(reg,bit)   reg &= ~(1<<bit)
 
void init_ports();
void lcd_set_4bit();
void lcd_init();
void lcd_wr_command(unsigned char);
void lcd_wr_char(char);
void lcd_home();
void lcd_cursor(char, char);
void lcd_print(char, char, unsigned int, int);
void lcd_string(char*);
 
unsigned int temp;
unsigned int unit;
unsigned int tens;
unsigned int hundred;
unsigned int thousand;
unsigned int million;
 
 
 
/*****Function to Reset LCD*****/
void lcd_set_4bit()
{
    _delay_ms(1);
 
    cbit(lcd_port,RS);              //RS=0 --- Command Input
    cbit(lcd_port,RW);              //RW=0 --- Writing to LCD
    _delay_ms(10);   
     lcd_port = 0x30;               //Sending 3
    _delay_ms(100); 
 
 
    sbit(lcd_port,EN);              //Set Enable Pin
    
    _delay_ms(20);                  //Delay
 
   
    cbit(lcd_port,EN);              //Clear Enable Pin
 
    _delay_ms(10);
 
    cbit(lcd_port,RS);              //RS=0 --- Command Input
    cbit(lcd_port,RW);              //RW=0 --- Writing to LCD
_delay_ms(100); 
    lcd_port = 0x30;                //Sending 3
_delay_ms(100);
 
    sbit(lcd_port,EN);              //Set Enable Pin
 
    _delay_ms(20);                  //Delay
    cbit(lcd_port,EN);              //Clear Enable Pin
 
    _delay_ms(10);
 
    cbit(lcd_port,RS);              //RS=0 --- Command Input
    cbit(lcd_port,RW);              //RW=0 --- Writing to LCD
 
 
    lcd_port = 0x30;                //Sending 3
_delay_ms(100);
    sbit(lcd_port,EN);              //Set Enable Pin
 
    _delay_ms(20);                  //Delay
    cbit(lcd_port,EN);              //Clear Enable Pin
 
    _delay_ms(10);
 
    cbit(lcd_port,RS);              //RS=0 --- Command Input
    cbit(lcd_port,RW);              //RW=0 --- Writing to LCD
 
    lcd_port = 0x20;                //Sending 2 to initialise LCD 4-bit mode
_delay_ms(100);
    sbit(lcd_port,EN);              //Set Enable Pin
 
 
    _delay_ms(20);                  //Delay
    cbit(lcd_port,EN);              //Clear Enable Pin
 
    
}
 
/*****Function to Initialize LCD*****/
void lcd_init()
{
    _delay_ms(10);
 
    lcd_wr_command(0x28);           //LCD 4-bit mode and 2 lines.
    _delay_ms(100);
    lcd_wr_command(0x01);
    _delay_ms(100);
    lcd_wr_command(0x06);
    
    _delay_ms(100);
    lcd_wr_command(0x0E);
    _delay_ms(100);
    lcd_wr_command(0x80);
    _delay_ms(100); 
}
 
     
/*****Function to Write Command on LCD*****/
void lcd_wr_command(unsigned char cmd)
{
    unsigned char temp;
    temp = cmd;
    temp = temp & 0xF0;
    lcd_port &= 0x0F;
    _delay_ms(100);
    lcd_port |= temp;
    _delay_ms(100);
    cbit(lcd_port,RS);
    cbit(lcd_port,RW);
    sbit(lcd_port,EN);
    _delay_ms(100);
    _delay_ms(5);
    cbit(lcd_port,EN);
    
    cmd = cmd & 0x0F;
    cmd = cmd<<4;
    lcd_port &= 0x0F;
    lcd_port |= cmd;
    _delay_ms(100);
    cbit(lcd_port,RS);
    cbit(lcd_port,RW);
    sbit(lcd_port,EN);
    
    _delay_ms(5);
    cbit(lcd_port,EN);
 
}
 
/*****Function to Write Data on LCD*****/
void lcd_wr_char(char letter)
{
    char temp;
    temp = letter;
    temp = (temp & 0xF0);
    lcd_port &= 0x0F;
    lcd_port |= temp;
_delay_ms(100);
    sbit(lcd_port,RS);
    cbit(lcd_port,RW);
    sbit(lcd_port,EN);
 
 
    _delay_ms(5);
    cbit(lcd_port,EN);
 
    letter = letter & 0x0F;
    letter = letter<<4;
    lcd_port &= 0x0F;
    lcd_port |= letter;
_delay_ms(100);
    sbit(lcd_port,RS);
    cbit(lcd_port,RW);
    sbit(lcd_port,EN);
 
    _delay_ms(20);
    cbit(lcd_port,EN);
 
}
 
 
void lcd_home()
{
    lcd_wr_command(0x80);
}
 
 
/*****Function to Print String on LCD*****/
void lcd_string(char *str)
{
    while(*str != '\0')
    {
        lcd_wr_char(*str);
        str++;
    _delay_ms(100);
    }
}
 
/*** Position the LCD cursor at "row", "column". ***/
 
void lcd_cursor (char row, char column)
{
    switch (row) {
        case 1: lcd_wr_command (0x80 + column - 1); break;
        case 2: lcd_wr_command (0xc0 + column - 1); break;
        case 3: lcd_wr_command (0x94 + column - 1); break;
        case 4: lcd_wr_command (0xd4 + column - 1); break;
        default: break;
    }
}
 
/***** Function To Print Any input value upto the desired digit on LCD *****/
void lcd_print (char row, char coloumn, unsigned int value, int digits)
{
    unsigned char flag=0;
    if(row==0||coloumn==0)
    {
        lcd_home();
    _delay_ms(100);
    }
    else
    {
        lcd_cursor(row,coloumn);
    }
    if(digits==5 || flag==1)
    {
        million=value/10000+48;
        lcd_wr_char(million);
        flag=1;
    }
    if(digits==4 || flag==1)
    {
        temp = value/1000;
        thousand = temp%10 + 48;
        lcd_wr_char(thousand);
        flag=1;
    }
    if(digits==3 || flag==1)
    {
        temp = value/100;
        hundred = temp%10 + 48;
        lcd_wr_char(hundred);
        flag=1;
    }
    if(digits==2 || flag==1)
    {
        temp = value/10;
        tens = temp%10 + 48;
        lcd_wr_char(tens);
        flag=1;
    }
    if(digits==1 || flag==1)
    {
        unit = value%10 + 48;
        lcd_wr_char(unit);
    }
    if(digits>5)
    {
        lcd_wr_char('E');
    }
    
}
        
int main()
 
{
DDRD=0b11111111;
 
lcd_init();
lcd_set_4bit();
 
 
 
int a=43;
while(1){
_delay_ms(200);
 
 
lcd_string("123456789 ");
 
}
 
 
 
}

 
Last edited by a moderator:

Dilpreet Singh

Junior Member level 1
Joined
Jan 21, 2015
Messages
19
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
155
i connect 10k pot to VEE , earlier it was shorted with vcc ,
but still not working
 

Ogu Reginald

Full Member level 6
Joined
Oct 7, 2011
Messages
369
Helped
47
Reputation
94
Reaction score
46
Trophy points
1,308
Location
Nigeria
Activity points
3,391
The first time I used the said LCD, after writing my code I simulated it using proteus and it was working as designed but when I constructed the hardware, it was not working.
I abandoned the project on my desk but I was doing something: every morning if I woke up I will go straight to the table and troubleshoot my connections and every night before I slept, I did the same thing.
One day I just discovered that melted lead alloy (for soldering) went and shorted three pins (EN, RS, RW). Immediately I seperated the three pins every thing worked well.

My advice for you since you have simulated your design virtually and it is working, make sure that all connections are the way they ought to be and check your delay function to see whether the delay is sufficient to be noticed in real life.
 

Dilpreet Singh

Junior Member level 1
Joined
Jan 21, 2015
Messages
19
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
155
i check connections and increase delay about 1 sec now , but not working yet
 

milan.rajik

Banned
Joined
Apr 1, 2013
Messages
2,528
Helped
540
Reputation
1,078
Reaction score
524
Trophy points
1,393
Activity points
0
Try this code. I have not tested it.


Code C - [expand]
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
/*
 * LCD_4_bit.c
 *
 * Created: 2/17/2015 1:04:20 AM
 *  Author: Jayanth Devarayanadurga
 */ 
 
#define F_CPU 400000
 
#include <avr/io.h>
#include <util/delay.h>
#include <string.h>
 
#define _LCD_FIRST_ROW          0x80     //Move cursor to the 1st row
#define _LCD_SECOND_ROW         0xC0     //Move cursor to the 2nd row
#define _LCD_THIRD_ROW          0x94     //Move cursor to the 3rd row
#define _LCD_FOURTH_ROW         0xD4     //Move cursor to the 4th row
#define _LCD_CLEAR              0x01     //Clear display
#define _LCD_RETURN_HOME        0x02     //Return cursor to home position, returns a shifted display to
                                         //its original position. Display data RAM is unaffected.
#define _LCD_CURSOR_OFF         0x0C     //Turn off cursor
#define _LCD_UNDERLINE_ON       0x0E     //Underline cursor on
#define _LCD_BLINK_CURSOR_ON    0x0F     //Blink cursor on
#define _LCD_MOVE_CURSOR_LEFT   0x10     //Move cursor left without changing display data RAM
#define _LCD_MOVE_CURSOR_RIGHT  0x14     //Move cursor right without changing display data RAM
#define _LCD_TURN_ON            0x0C     //Turn Lcd display on
#define _LCD_TURN_OFF           0x08     //Turn Lcd display off
#define _LCD_SHIFT_LEFT         0x18     //Shift display left without changing display data RAM
#define _LCD_SHIFT_RIGHT        0x1E     //Shift display right without changing display data RAM
 
#define RS 0
#define EN 2
#define LCD_PORT PORTD
 
#define sbit(reg,bit)   reg |= (1<<bit)
#define cbit(reg,bit)   reg &= ~(1<<bit)
 
void LCD_Init();
void LCD_Cmd(char);
void LCD_Chr(char, char, char);
void LCD_Chr_Cp(char);
void LCD_Out(char, char, char*);
void LCD_Out_Cp(char*);
 
void lcd_print(char, char, unsigned int, int);
 
void LCD_Init() {
 
    _delay_ms(100);
    
    cbit(LCD_PORT,RS);              //RS=0 --- Command Input
        
    LCD_PORT = 0x30;               //Sending 3
    sbit(LCD_PORT,EN);              //Set Enable Pin
    _delay_us(50);                  //Delay
    cbit(LCD_PORT,EN);              //Clear Enable Pin
    
    _delay_ms(30);
        
    LCD_PORT = 0x30;               //Sending 3
    sbit(LCD_PORT,EN);              //Set Enable Pin
    _delay_us(50);                  //Delay
    cbit(LCD_PORT,EN);              //Clear Enable Pin
    
    _delay_ms(30);             //Clear Enable Pin
            
    LCD_PORT = 0x30;               //Sending 3
    sbit(LCD_PORT,EN);              //Set Enable Pin
    _delay_us(50);                 //Delay
    cbit(LCD_PORT,EN);              //Clear Enable Pin
    
    _delay_ms(30);            //Clear Enable Pin
            
    LCD_PORT = 0x20;               //Sending 3
    sbit(LCD_PORT,EN);              //Set Enable Pin
    _delay_us(50);                  //Delay
    cbit(LCD_PORT,EN);              //Clear Enable Pin
    
    _delay_ms(30);             //Clear Enable Pin
    
    LCD_Cmd(0x28);
    LCD_Cmd(0x0C);  
}
 
void LCD_Cmd(char out_char) {       
    cbit(LCD_PORT,RS);
        
    LCD_PORT = out_char & 0xF0;
        
    sbit(LCD_PORT,EN);
    _delay_us(50);
    cbit(LCD_PORT,EN);
    
    LCD_PORT = (out_char & 0x0F) << 4;
    
    sbit(LCD_PORT,EN);
    _delay_us(50);
    cbit(LCD_PORT,EN);  
}
 
void LCD_Chr(char row, char column, char out_char) {
    
    switch (row) {
        case 1: LCD_Cmd (0x80 + column - 1); break;
        case 2: LCD_Cmd (0xc0 + column - 1); break;
        case 3: LCD_Cmd (0x94 + column - 1); break;
        case 4: LCD_Cmd (0xD4 + column - 1); break;     
    };
        
    sbit(LCD_PORT,RS);  
        
    LCD_PORT = out_char & 0xF0;
    
    sbit(LCD_PORT,EN);
    _delay_us(50);
    cbit(LCD_PORT,EN);
    
    LCD_PORT = (out_char & 0x0F) << 4;
    
    sbit(LCD_PORT,EN);
    _delay_us(50);
    cbit(LCD_PORT,EN);  
}
 
void LCD_Chr_Cp(char out_char) {
    
    sbit(LCD_PORT,RS);
    
    LCD_PORT = out_char & 0xF0;
    
    sbit(LCD_PORT,EN);
    _delay_us(50);
    cbit(LCD_PORT,EN);
    
    LCD_PORT = (out_char & 0x0F) << 4;
    
    sbit(LCD_PORT,EN);
    _delay_us(50);
    cbit(LCD_PORT,EN);
}
 
void LCD_Out(char row, char column, char *str) {
    while(*str)
        LCD_Chr(row, column, *str++);   
}
 
void LCD_Out_Cp(char *str) {
    while(*str)
        LCD_Chr_Cp(*str++);
}
 
int myInt = 255;
char str[17];
 
int main() {
 
    DDRD = 0b11111111;
    PORTD = 0x00;
    
    LCD_Init();
    LCD_Cmd(_LCD_CURSOR_OFF);
    LCD_Cmd(_LCD_CLEAR);    
    
    LCD_Out(1,1,"ATMega32");
    LCD_Out(2,1,"LCD 4 bit");
    LCD_Out(3,1,"16x2, 20x2, 20x4");
    LCD_Out(4,1,"Testing...");
    
    _delay_ms(5000);
    LCD_Cmd(_LCD_CLEAR);    
    
    itoa(myInt, str, 10);
    LCD_Out(1,1,str);
    
    while(1){
                    
    }   
}

 

Dilpreet Singh

Junior Member level 1
Joined
Jan 21, 2015
Messages
19
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
155
atmega8 Sir ....

- - - Updated - - -

And is there is a need to gnd the remaing 4 data pins which are unused ? ie D0 to D3 Of LCD
 

Ogu Reginald

Full Member level 6
Joined
Oct 7, 2011
Messages
369
Helped
47
Reputation
94
Reaction score
46
Trophy points
1,308
Location
Nigeria
Activity points
3,391

ud23

Advanced Member level 3
Joined
Apr 20, 2011
Messages
926
Helped
185
Reputation
370
Reaction score
180
Trophy points
1,323
Activity points
6,138

Dilpreet Singh

Junior Member level 1
Joined
Jan 21, 2015
Messages
19
Helped
0
Reputation
0
Reaction score
0
Trophy points
1
Activity points
155
yes there is problem with delays as well as with potentiometer , Now it is solved
THANKS EVERY ONE
 

Status
Not open for further replies.

Similar threads

Part and Inventory Search

Welcome to EDABoard.com

Sponsor

Top