[SOLVED] Problem in default arithmetic for ' i ' variable.

[WhyWhy]

Hi guys,

I not set any arithmetic such as int,char or float for the ' i ' variable.When execute the program still the having delay function,so the default arithmetic for the i will be int,char or float ?



Regards,
YY

 

[Venkadesh_M]

Hi you are using which compiler?? no C compiler declares the variables by default, You have to mention it to be a variable. There is no way compiling this program without i being global variable...

Seeing at value of i compared with 20000 It shd be an int value..

 

[nick703]

is that your program run complete or not?

 

[embpic]

whare you have declare variable i?

 

[WhyWhy]

HI Guys,

But the program is run successfully,that is the reason why i asking here...

Regards,
YY

 

[nick703]

put some different variable and test the result ?

 

[embpic]

redefine this variable and check wheather warning is there or not
and check the included file is same which one your checking.

 

[keith1200rs]

Some compilers will assume a default and give a warning rather than error - check the compile warnings. You have not said which compiler.

Keith

 

[Venkadesh_M]

Some compilers will assume a default and give a warning rather than error - check the compile warnings.
Keith

But How could the program running correctly by taking i as a variable??

 

[nagkiller]

Try this:

//**********************************************************************************************************
// Hitech C
//**********************************************************************************************************
#include <pic.h>
//**********************************************************************************************************
__CONFIG ( FOSC_XT & WDTE_OFF & PWRTE_OFF & CP_OFF );
//**********************************************************************************************************
void delay()
{
unsigned int i;
	for (i =0; i<20000; i++)
	{
		NOP();
	}
}
//**********************************************************************************************************
void main()
{
		TRISB = 0;
		PORTB = 0;
		while(1)
		{
			CLRWDT();
			RB0=0;
			delay();
			RB0=1;
			delay();
		}
}
//**********************************************************************************************************

Or this

//**********************************************************************************************************
// Hitech C
//**********************************************************************************************************
#include <pic.h>
//**********************************************************************************************************
__CONFIG ( FOSC_XT & WDTE_OFF & PWRTE_OFF & CP_OFF );
//**********************************************************************************************************
#ifndef _XTAL_FREQ
 // Unless already defined assume 4MHz system frequency
 // This definition is required to calibrate __delay_us() and __delay_ms()
 #define _XTAL_FREQ 4000000
#endif
//**********************************************************************************************************
void main()
{
		TRISB = 0;
		PORTB = 0;
		while(1)
		{
			CLRWDT();
			RB0=0;
			__delay_ms(200);
			RB0=1;
			__delay_ms(200);
		}
}
//**********************************************************************************************************

 

[Venkadesh_M]

with htc it shows error...

 

[keith1200rs]

But How could the program running correctly by taking i as a variable??

i should be a variable - an 'int'. Some compilers will assume undeclared ones are 'int'. XC16 does that if you don't include a function prototype but it does warn you. You can probably change the settings so it gives an error instead.

Keith

 

[nick703]

hey Nagkiller i think u don't understand problem because problem is he does not declare any variable i in his code and then program successfully run . bro WhyWhy mentioned post no . # 5 and i also suggest put some different variable like j , k and try it run or not ?

 

[nagkiller]

My variable is temp or something and provide same result!!!

In my compiler has error "undefined identifier "i"", if not declare a variable!!!

My version of hitech is V9.83 pro!!!

And post is #6!!!

The compiler generate hex???

 

[Venkadesh_M]

i should be a variable - an 'int'. Some compilers will assume undeclared ones are 'int'. XC16 does that if you don't include a function prototype but it does warn you. You can probably change the settings so it gives an error instead.

Keith

Hi i didnt change any settings... It could declare a function, most compilers will do, but how could a variable been declared...

 

[nick703]

My variable is temp or something and provide same result!!!

In my compiler has error "undefined identifier "i"", if not declare a variable!!!

And post is #6!!!

The compiler generate hex???

it's not your compiler generate undefined identifier "i" bro my and all c compiler is also generated same message but question is why WHYWHY said program run successfully ????



EDIT:

better way is WHYWHY put your complete project file to zip and place here.

 

[Venkadesh_M]

it's not your compiler generate undefined identifier "i" bro my compiler is also generated same message but question is why WHYWHY said program run successfully ????.

Not only your compiler, every C compiler will do so, unless i is a controller register defined in header file..

 

[nagkiller]

Exactly!!!

This is extremely strange!!!

 

[nick703]

i know Venkadesh_M sorry to use my compiler !!! edited

 

[jayanth.devarayanadurga]

The header file indicates that it is Hi-Tech C Compiler.