Led number display

[Usman]

Salam , 

I am using PIC18f458 

i wrote a code to display  led number but code is not entering in to the if statement 

what is the problem here???

code is here 

 

#include<pic18.h>

#define ldata PORTD

#define rs PORTBbits.RB0

#define rw PORTBbits.RB1

#define en PORTBbits.RB2

#define led1 PORTAbits.RA0

#define led2 PORTAbits.RA1

#define led3 PORTAbits.RA2

 

void lcdcmd(unsigned char );

void lcddata();

void MsDelay(unsigned int );

void main() 

{

 

// unsigned char message=”Usman Salleem “;

TRISD=0;       // make an output port

TRISB=0;

TRISAbits.TRISA0=0;

TRISAbits.TRISA1=0;

TRISAbits.TRISA2=0;

en=0;

// led1=1;

// led2=1;

// led3=1;

MsDelay(250);

lcdcmd(0x38);

MsDelay(250);

lcdcmd(0x0E);

MsDelay(15);

lcdcmd(0x01);

MsDelay(15);

lcdcmd(0x06);

MsDelay(15);

lcdcmd(0x80);

MsDelay(15);

 

lcddata();

// MsDelay(1000);

// lcddata(‘d’);

// MsDelay(1000);

// lcddata(‘e’);

 

}

 

void lcdcmd(unsigned char value )

{

ldata=value ; 

rs=0;

rw=0;

en=1;

MsDelay(1);

en=0;

}

 

/*void lcddata()

{

unsigned char message[]=”Earth is one Land “;

unsigned char z ; 

for(z=0; z<17; z++)

{

ldata=message[z];

// MsDelay(100);

rs=1;

rw=0;

en=1;

MsDelay(1);

en=0;

}

}

*/

 

void lcddata()

{

 

unsigned char z ; 

unsigned char  message1[]=”LED 1 is ONN”;

unsigned char  message2[]=”LED 2 is ONN”;

unsigned char  message3[]=”LED 3 is ONN”;

unsigned char  message4[]=”Nothing is ONN”;

unsigned char f ; 

// led1=0;

led1=1;

led2=0;

led3=0;

 

if ((led1==1  || led2 && led3 == 0)==1)

{

for(z=0; z<12; z++)

{

ldata=message1[z];

rs=1;

rw=0;

en=1;

MsDelay(1);

en=0;

}

}

else if (led2==1)

{

for(z=0; z<12; z++)

{

ldata=message2[z];

rs=1;

rw=0;

en=1;

MsDelay(1);

en=0;

}

}

  else if(led3==1)

{

for(z=0; z<12; z++)

{

ldata=message3[z];

rs=1;

rw=0;

en=1;

MsDelay(1);

en=0;

}

}

 

 

else   if(led1==0 && led2==0 && led3==0)

{

for(z=0; z<14; z++)

{

ldata=message4[z];

rs=1;

rw=0;

en=1;

MsDelay(1);

en=0;

 

}

}

 

 

}

 

void MsDelay(unsigned int itime )

{

unsigned int i , j ; 

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

for(j=0; j<135; j++);

 

}

 

[AJISH ALFRED]

Hi Usman,

Using the statement if ((led1==1  || led2 && led3 == 0)==1) you are trying to read port bits 0,1 and 2 of port A which are already set as output. It is always better to avoid reading an output port.

Again you should always careful about using proper brackets like;

if ( ( ( led1==1 )  || ( ( led2 && led3 ) == 0 )  ) ==1 )

[Usman]

Hi  Dear,

 

actually problem is that 

 

when i write a code like that 

 

 

led1=1;

                          if(led1==1)

                             {

                                           display message

                               }

but problem is compiler is not reading the if and its ignore this statement , even this is a true statement 

and goes to else 

 

[AJISH ALFRED]

Hi Usman,

I’ve once faced the same issue with the nested if-else. The problem got fixed by adding ‘else’ for evry ‘if’.

When there is an ‘if’ there should be an ‘else’ eventhough there is nothing in the ‘else’ statement.

Coming to your code, the last ‘else-if’ condition is not terminated with an ‘else’.

Suggest you to add an ‘else’ like the following;

 

 

if ((led1==1  || led2 && led3 == 0)==1)

{

for(z=0; z<12; z++)

{

ldata=message1[z];

rs=1;

rw=0;

en=1;

MsDelay(1);

en=0;

}

}

else if (led2==1)

{

for(z=0; z<12; z++)

{

ldata=message2[z];

rs=1;

rw=0;

en=1;

MsDelay(1);

en=0;

}

}

  else if(led3==1)

{

for(z=0; z<12; z++)

{

ldata=message3[z];

rs=1;

rw=0;

en=1;

MsDelay(1);

en=0;

}

}

 

 

else   if(led1==0 && led2==0 && led3==0)

{

for(z=0; z<14; z++)

{

ldata=message4[z];

rs=1;

rw=0;

en=1;

MsDelay(1);

en=0;

 

}

} else;                                 // HERE //

 

Please try and update the result.

 

[Author]

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