problem Interfacing 16x2 lcs display with at89c51 microcontroller

[kaus9952083382]

sir i have interface 16x2 lcd display with microcontroller at89c51 and it is working fine in proteus as well as keil compiler ... but when i m burning hex code and interfacing with my hardware i am not able to get the output .... i m posting my coding over here .... please help me out ... thanks in advance


#include<reg51.h>
#define dp P0
sbit rs=P0^1;
sbit en=P0^2;
sbit rw=P0^3;
lcdcomm(unsigned char val);
lcddat(unsigned char val);
msdelay(unsigned int val);
write_nibble(unsigned int val);

unsigned char mydat[]="hello kaushal";
unsigned char urdat[]="hello amit";

main()
{
P0=0xff;
msdelay(10);
lcdint();
lcdcomm(0x01);
msdelay(1);
lcdcomm(0x80);
msdelay(1);
lcddat('*');
msdelay(1);
lcdcomm(0x82);
msdelay(1);
dis_measure();
lcdcomm(0xc2);
msdelay(1);
dis_d_t();
}

unsigned char z;

lcdint()
{
rs=0;
rw=0;
dp=0x28;

en=1;
msdelay(1);
en=0;
msdelay(1);

lcdcomm(0x28);
msdelay(1);

lcdcomm(0x0f);
msdelay(1);
}

dis_measure()
{
unsigned char z;
for(z=0;z<=15;z++)
{
lcddat(urdat[z]);
msdelay(1);
}

}
dis_d_t()
{
unsigned char z;
for(z=0;z<=15;z++)
{
lcddat(mydat[z]);
msdelay(1);
}

}


/********************************/

lcdcomm(unsigned char val)
{
rs=0;
rw=0;
write_nibble();
}

/*****************************/

lcddat(unsigned char val)
{
rs=1;
rw=0;
write_nibble();
}

/**************************/

msdelay(unsigned int val)
{
unsigned int i,j;
for(i=0;i<=val;i++)
for(j=0;j<=200;j++);
}

/************************/

write_nibble(unsigned int val)
{
unsigned char i,j,k;
i=val&0xf0;
j=dp&0x0f;
dp=j|i;
en=1;
msdelay(1);
en=0;
msdelay(1);
val=val<<4;
i=val&0xf0;
k=dp&0x0f;
dp=k|i;
en=1;
msdelay(1);
en=0;
msdelay(1);
}

 

[Li_ereunpisan]

if the simulated in proteus really means a problem in the hardware
check u're hardware ...
make sure that the pins RS conected to p0.1
pins E conected to p0.2
pins RW conected to p0.3,and
pin data D0-D7

 

[thannara123]

put your circuit

 

[kaus9952083382]

sir i m sure tht i have connected the pins properly ... nd one more thing i removed the rw pin from Port 0^3 and grounded it as it is not required in 4 bit operation

 

[freddyp007]

Check whether you have connected the data pins of the LCD in order. i.e. D0 to P1_0; D1 to P1_1 etc. Maybe you got every connection ok. Then check the microcontroller by writing a simple test program.

 

[kaus9952083382]

sir this is my new coding and circuit diagram.....

#include<reg51.h>
#define dp P2
sbit rs=P1^0;
sbit en=P1^1;
lcdcomm(unsigned char val);
lcddat(unsigned char val);
msdelay(unsigned int val);
write_nibble(unsigned int val);

unsigned char mydat[]="hello kaushal";
unsigned char urdat[]="hello amit";

main()
{
P2=0xff;
msdelay(20);
lcdint();
lcdcomm(0x01);
msdelay(10);
lcdcomm(0x80);
msdelay(1);
lcddat('*');
msdelay(1);
lcdcomm(0x82);
msdelay(1);
dis_measure();
lcdcomm(0xc2);
msdelay(1);
dis_d_t();
}

unsigned char z;

lcdint()
{
rs=0;
dp=0x28;

en=1;
msdelay(20);
en=0;
msdelay(10);

lcdcomm(0x28);
msdelay(1);

lcdcomm(0x0f);
msdelay(1);
}

dis_measure()
{
unsigned char z;
for(z=0;z<=15;z++)
{
lcddat(urdat[z]);
msdelay(10);
}

}
dis_d_t()
{
unsigned char z;
for(z=0;z<=15;z++)
{
lcddat(mydat[z]);
msdelay(10);
}

}


/********************************/

lcdcomm(unsigned char val)
{
rs=0;
write_nibble();
}

/*****************************/

lcddat(unsigned char val)
{
rs=1;
write_nibble();
}

/**************************/

msdelay(unsigned int val)
{
unsigned int i,j;
for(i=0;i<=val;i++)
for(j=0;j<=200;j++);
}

/************************/

write_nibble(unsigned int val)
{
unsigned char i,j,k;
i=val&0xf0;
j=dp&0x0f;
dp=j|i;
en=1;
msdelay(10);
en=0;
msdelay(10);
val=val<<4;
i=val&0xf0;
k=dp&0x0f;
dp=k|i;
en=1;
msdelay(10);
en=0;
msdelay(10);
msdelay(200);
}

 

[freddyp007]

Where is the circuit diagram mate?

 

[Li_ereunpisan]

try to plug the pull-up resistors on the port you use

 

[kaus9952083382]

this is my hardware circuit.....

 

[freddyp007]

this is my hardware circuit.....

View attachment 63711

:!:Whenever you use the internal flash-ROM of 8051, connect the EA(pin 31) to VCC. If at all you need an external ROM you have to ground it since it is active 'low'.
So, in the hardware connect pin 31 to VCC.

P.S. Proteus does not take that into account, so you got the result in simulation

 

[kaus9952083382]

Sir .... I have corrected connected the pin .... Even varied the delay ..... But it is still not working

 

[Li_ereunpisan]

I agree freddy.....
whether the EA pin (31) is connected to VCC?
EA pin (31) must be connected to VCC

 

[kaus9952083382]

now i have made the connection proper .... is there a problem with delay

 

[ark5230]

Now it seems the pull-up resistors to the ports in use are missing. This could be the reason if rest is OK.