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Problem in C coding of 89c51; urgent help required.

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Qaisar Azeemi

Qaisar Azeemi

Member
Hi all;

i have interfaced lcd and adc with my 89c51 controller and want to make a digital thermometer, that display the temprature in both C and F scales. i write code for it but got the following problems.

DVM(8): error C202: 'Port': undefined identifier
DVM(9): error C202: 'Port': undefined identifier
DVM(10): error C202: 'Port': undefined identifier
DVM(11): error C202: 'Port': undefined identifier
DVM(12): error C202: 'Port': undefined identifier
DVM(13): error C202: 'Port': undefined identifier
DVM(14): error C202: 'Port': undefined identifier
DVM(35): error C202: 'RS': undefined identifier
DVM(36): error C202: 'E': undefined identifier
DVM(38): error C202: 'E': undefined identifier
DVM(49): error C202: 'RS': undefined identifier
DVM(50): error C202: 'E': undefined identifier
DVM(52): error C202: 'E': undefined identifier
DVM(59): error C141: syntax error near 'char', expected ')'
DVM(62): error C202: 'str': undefined identifier
DVM(64): error C202: 'str': undefined identifier
DVM(190): error C202: 'ALE': undefined identifier
DVM(191): error C202: 'SC': undefined identifier
DVM(194): error C202: 'ALE': undefined identifier
DVM(196): error C202: 'SC': undefined identifier
DVM(199): error C202: 'ALE': undefined identifier
DVM(201): error C202: 'SC': undefined identifier
DVM(213): error C202: 'test_inermediate2': undefined identifier
Target not created






i searched it out but cant solve it.
here is my code.......




Code: 
#include <reg51.h>

#define port P3 // control port
#define adc_input P1
#define data_port P0 // data from microcontroller to LCD


sbit ADC_A=Port^0; //ADC
sbit ADC_B=Port^1; //ADC
sbit RS=Port^2; //LCD
sbit E=Port^3; //LCD
sbit SC=Port^4; //ADC
sbit CLK=Port^5; //ADC
sbit ALE=Port^6; //ADC

int test_intermediate3=0, test_final=0;
int test_intermediate1[10], test_intermediate2[3]={0,0,0};

//------------------- . ------------------

void delay(unsigned int msec)
{
int i,j;
for(i=0; i=msec; i++)
for(j=0; j=1275; j++);

}

//.................. LCD .................


void lcd_cmd( unsigned int item )
{
data_port=item; //command on data port p0 of lcd
RS=0; // selecting command register of lcd
E=1;
delay(1);
E=0;
return;


}



void lcd_data( unsigned int item )
{
data_port=item; //data on data port p0 of lcd
RS=1; // selecting data register of lcd
E=1;
delay(1);
E=0;
return;


}


void lcd_data_string(usinged char *str) // sending string to LCD
{
int i=0;
while (str[i] != '\0')
{
lcd_data(str[i]);
i++;
delay(10);
return;

}

}


//----------- custom character Generation for Degree symbol-----------

void shape()
{

lcd_cmd(64); // first location in CGRAM
lcd_cmd(2);
lcd_cmd(5);
lcd_cmd(2);
lcd_cmd(0);
lcd_cmd(0);
lcd_cmd(0);
lcd_cmd(0);
lcd_cmd(0);

return;
}



// Converting binary value of ADC to ASCII value of LCD

void convert()
{
int s;
lcd_cmd(0x81);
delay(2);
lcd_data_string("Temp: "); // Farnheit conversion

test_final=(((9*test_intermediate3)/5)+32);

s=test_final/100;
test_final=test_final%100;

lcd_cmd(0x88);
if (s!=0)
lcd_data(s+48);
else
lcd_cmd(0x06);



s=test_final/10;
test_final=test_final%10;

lcd_data(s+48);
lcd_data(test_final+48);
lcd_data(0);
lcd_data('F');
lcd_data(' ');


//------------------- for Celcius scale----------------

test_final=test_intermediate3;

lcd_cmd(0xC1); // set cursor to second line.
delay(2);
lcd_data_string("Temp: ");
s=test_final/100;
test_final=test_final%100;

lcd_cmd(0xc8);
if (s!=0)
lcd_data(s+48);
else
lcd_cmd(0x06);



s=test_final/10;
test_final=test_final%10;

lcd_data(s+48);
lcd_data(test_final+48);
lcd_data(0);
lcd_data('C');
lcd_data(' ');

delay(2);

}








//.........--------.......Main Program.......-------........








void main()
{

int i,j;
adc_input=0xff ; // making p1 as input port
lcd_cmd(0x38);
lcd_cmd(0x0c);
delay(2);
lcd_cmd(0x01);
delay(2);
while(1)
{
for(j=0;j<3;j++)
{
for(i=0;i<10;i++)
{
delay(1);
ALE=0;
SC=0;
delay(1);

ALE=1;
delay(1);
SC=1;
delay(1);

ALE=0;
delay(1);
SC=0;
delay(4);

lcd_cmd(0x88);

test_intermediate1[i]=adc_input/10;
delay(1);

}


for(i=0;i<10;i++)
test_inermediate2[j]+=test_intermediate1[i];
}


test_intermediate2[0]=test_intermediate2[0]/3;
test_intermediate2[1]=test_intermediate2[1]/3;
test_intermediate2[2]=test_intermediate2[2]/3;

test_intermediate3=test_intermediate2[0] + test_intermediate2[1] + test_intermediate2[2];

shape();

convert();
}
}






please help me to solve my problem.

Thank you
 
Last edited by a moderator:
Thank you very much fellows....

the problem is solved with your provided help.... Thanks a lot again.

acctually this is my first time that i make a complete program in C... which is not pure my own... but it is my practice...



The above program is successfully compiled but now the problem is that it is not simulating in proteous... outputs of the controller are quite still, no movement and no change in the output pin bits is seen.. every signal is quite still and stuck.... i have used infinite while loop in main and also scanning the ADC channel 0 continuously... but can't understand the problem???
 
you mean connecting resistora and capasitor to the reset pin of the controller.....

if yes then hardware assembly is OK, i connect it with reset pin of 89c51 and it is running other programs. i think problem is in my code.
 
i make the following code to make a thermometer but i got the problem in the output at port 0 which is stuck and still at lcd_cmd(0x38) command in main program.

following is the code.


Code: 
#include <reg52.h>


 #define Port P3  // control port
 #define adc_input P1
 #define data_port P0  // data from microcontroller to LCD
 #define sec=100

 sbit ADC_A=Port^0;	//ADC
 sbit ADC_B=Port^1;	//ADC
 sbit RS=Port^2;  		//LCD
 sbit E=Port^3;		   //LCD
 sbit SC=Port^4;   //ADC
 sbit CLK=Port^5;  //ADC
 sbit ALE=Port^6;  //ADC

int test_intermediate3=0, test_final=0;
int test_intermediate1[10], test_intermediate2[3]={0,0,0};

		 //------------------- . ------------------

		void delay(unsigned int msec)
		{
			int i,j;
			for(i=0; i=msec; i++)
				for(j=0; j=1275; j++);

		}




		//---------------- timer 0 interrupt----------------

		void timer0() interrupt 1
		{
		   		
					CLK=~CLK;		// Toggle port bit p3.5
					TR0=0;         // stop timer
					TH0=0xff;	    // 500hz clock for adc
					TL0=0xff;
					TR0=1;			// start timer
		}



		//.................. LCD .................


		void lcd_cmd( unsigned int item )
		{
			data_port=item;  //command on data port p0 of lcd
			RS=0; // selecting command register of lcd
			E=1;
			delay(10);
			E=0;
			return;
		}




		void lcd_data( unsigned int item )
		{
			data_port=item;  //data on data port p0 of lcd
			RS=1; // selecting data register of lcd
			E=1;
			delay(10);
			E=0;
			return;
		}



	  void lcd_data_string(unsigned char *str)  // sending string to LCD
	  {
	  		int i=0;
			while (str[i] != '\0')
				{
					lcd_data(str[i]);
					i++;
					delay(10);
					return;

				}
	  
	  }


	  //----------- custom character Generation for Degree symbol-----------

	  void shape()
	  {
	  		
			lcd_cmd(64); // first location in CGRAM
			lcd_cmd(2);
			lcd_cmd(5);
			lcd_cmd(2);
			lcd_cmd(0);
			lcd_cmd(0);
			lcd_cmd(0);
			lcd_cmd(0);
			lcd_cmd(0);

			return;
	  }



	  // Converting binary value of ADC to ASCII value of LCD

	  void convert()
	  {
	  		int s;
			lcd_cmd(0x81);
			delay(2);
			lcd_data_string("Temp: ");   // Farnheit conversion

			test_final=(((9*test_intermediate3)/5)+32);
			
			s=test_final/100;
			test_final=test_final%100;

			lcd_cmd(0x88);
			if (s!=0)
			lcd_data(s+48);
			else
			lcd_cmd(0x06);



		  s=test_final/10;
		  test_final=test_final%10;

		  lcd_data(s+48);
		  lcd_data(test_final+48);
		  lcd_data(0);
		  lcd_data('F');
		  lcd_data(' ');


		//------------------- for Celcius scale----------------

		  test_final=test_intermediate3;

		  lcd_cmd(0xC1);  // set cursor to second line.
		  delay(2);
		  lcd_data_string("Temp: ");
		  s=test_final/100;
			test_final=test_final%100;

			lcd_cmd(0xc8);
			if (s!=0)
			lcd_data(s+48);
			else
			lcd_cmd(0x06);



		  s=test_final/10;
		  test_final=test_final%10;

		  lcd_data(s+48);
		  lcd_data(test_final+48);
		  lcd_data(0);
		  lcd_data('C');
		  lcd_data(' ');

		  delay(2);

	  }








	  //.........--------.......Main Program.......-------........








		   void main()
		   {

		   		int i,j;
				adc_input=0xff; // making p1 as input port
				TMOD=0x01;	   // timer 0,  mode 1
				TH0=0xff;	    // 500hz clock for adc
				TL0=0xff;
				TR0=1;         // timer start

				IE=0x82;		// interrupt enable ; timer interrupt and globle interrupt.
				
				lcd_cmd(0x38);		// initializing LCD module
					
				lcd_cmd(0x0c);
				
				lcd_cmd(0x01);
				
				lcd_cmd(0x06);
				
				lcd_cmd(0x81);

				lcd_data_string("Temp: ");

				while(1)
				{
						for(j=0;j<3;j++)
						{
							for(i=0;i<10;i++)
							{
								   ADC_A=0;
								   ADC_B=0; // channel 0 is selected

									delay(1);
									ALE=0;
									SC=0;
									delay(1);

									ALE=1;
									delay(1);
									 SC=1;
									 delay(1);

									 ALE=0;
									 delay(1);
									 SC=0; 
									 delay(4);

									 lcd_cmd(0x88);

									 test_intermediate1[i]=adc_input/10;
									 delay(1);

							}


							for(i=0;i<10;i++)
							test_intermediate2[j]+=test_intermediate1[i];
						}


						test_intermediate2[0]=test_intermediate2[0]/3;
						test_intermediate2[1]=test_intermediate2[1]/3;
						test_intermediate2[2]=test_intermediate2[2]/3;

						test_intermediate3=test_intermediate2[0] + test_intermediate2[1] + test_intermediate2[2];

						shape();

						convert();
				}
		   }

and following is the immage of the ckt in proteous:

View attachment 61563

i am tring to solve it from many hours but still im faild... i cant understand what the problem is in my code??? i need urgent help plz... :-(
 
Code: 
void delay(unsigned int msec)
		{
			int i,j;
			for(i=0; i=msec; i++)     ----------->> Whoops... this is the assignment operator.....You need to check for equality  '==' 
				for(j=0; j=1275; j++);
 
		}

Change to
Code: 
void delay(unsigned int msec)
		{
			int i,j;
			for(i=0; i==msec; i++)
				for(j=0; j==1275; j++);
 
		}

Or the variables will just sit at the same value.
 
Thank you Mr Ian thanks a lot... i did it :)

problem solved after your recommended changes.

but still some logical problems are there that i will post here tomarrow :)

Thanks a lot again.
 
Can you please give me any routine to dispaly Temp: on my lcd screen... here in my program it is displaying only T... the code is as follows.

Code: 
void lcd_data_string(unsigned char *str)  // sending string to LCD
	  {
	  		int i=0;
			while (str[i] != '\0')
				{
					lcd_data(str[i]);
					i++;
					delay(10);
					return;
 
				}


and to call this i am using :

Code: 
lcd_data_string("Temp: ");

please help.
 
My routines are a tad shorter

Code: 
void lcd_data_string(unsigned char *str)  // sending string to LCD
	  {
	  while (*str  != '\0')
		{
		lcd_data(*str++);
		delay(10);
		}
	}

You don't need a return as the function is void.
 
Thank you Ian...
and how to calculate the delay time of this function. my Xtal oscillator is 12MHz.

Code: 
void delay(unsigned int msec)
		{
			int i,j;
			for(i=0; i==msec; i++)
				for(j=0; j==1275; j++);

		}
 
12mhz on a chip that has 12 clocks per instruction.... 1 million instructions per second.... 1/1000000 = 1uS, 1000 * 1uS = 1mS.... so you need to count 1000 times.... BUT!!!! the for loop will take quite a few clock cycles AND you are increasing a word not a byte... this will be about 6 clock cycles (possibly more) .. so 1000 / 6 = 167 ... Start with 167 on the J loop ( remember to deduct the same amount from the I loop ).. Pass 1 to the delay loop (have you a simulator?) and 1000 to the delay loop.. and check it.
 
i have proteous and multisim EWB...
how to check the execution of code there...

and from your explained post above i come to know that the above loop is for 1 msec if i pass 1 to the funtion. am i right???
 
I have just simulated the for loop and the for loop takes 7 clock cycles..... if j ==167 gives 1.17 mS So you'll have to go a tad smaller.... Say j == 143 (1.001mS) ... works out near enough... But remember the 'i' for loop takes 7uS to execute as well, so each iteration will need adjustment of 7uS per call, so 142 will be better.
 
Last edited:
how can i samulate it to know the execution times.. please post the steps and also what compilar and Simulation software are you using??
 
You don't need to now... I've done it....I have MCU 8051 IDE with SDCC.... works pretty well... it doesn't chuck out a coff file for debugging but there is a simulator in the IDE...The hex file goes directly into proteus.
 
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