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load an address to a pointer variable

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Dinuwilson

Dinuwilson

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main()
{
int *a;
in my program i want to load the vale 0x06 as an address to pointer variable a

how can i load the value 0x06 to pointer variable a


please help me to solve this problam
 

thanks for your replay, i am use this code for pic microcontroller programming.

this is my code

#include<pic.h>

void main()
{
int *a;
TRISB=0X00;
int *a = (int *) 0x06 ;
a=0xFF;

}

here ox06 is the address of PORTB. i want to pass the value 0xFF to PORTB using
pointers.
 

Dinuwilson said:
thanks for your replay, i am use this code for pic microcontroller programming.

this is my code

#include<pic.h>

void main()
{
int *a;
TRISB=0X00;
int *a = (int *) 0x06 ;
a=0xFF;

}

here ox06 is the address of PORTB. i want to pass the value 0xFF to PORTB using
pointers.
Click to expand...
in
Code: 
    int *a = (int *) 0x06 ;
    a=0xFF;
you initialize a with the value 0x06 then assign it the value 0xFF, i.e. a now points to address 0xFF
you need to use the * operator to dereference a when you use it to write to port B, i.e.
Code: 
    int *a = (int *) 0x06 ;
    *a=0xFF;
write 0xFF to address 0x06
 
if i use

int *a = (int *) 0x06 ;
*a=0xFF;

in mplab it show error. here i attach the error shows in mplab. error.JPG
 

running the following code (built using MPLAB 8.86 and HI-TECH C Compiler for PIC10/12/16 MCUs (Lite Mode) V9.83)
Code: 
#include <htc.h>

// delay function
void delay(int x)
{
	int i;
	for(i=0;i<10000;i++);
}

void main(void)
{
	unsigned char* portb=0x06;      // port B 
 	TRISB=0;
	*portb=0;
     while(1)
 		{
		delay(1000);
		*portb=!*portb;		// blink LED on portB
		}
}
on a PICDEM mechatronics board
**broken link removed**

it blinks LEDs connected to PORTB

not sure what you problem is - MPLAB should not crash! perhaps reinstall it and the complier
 

same error shows when i use you codeerror.JPG

- - - Updated - - -

same error shows when i use your codeerror.JPG
 

the following
Code: 
#include <pic.h>

void main(void)
{
	int *a;
	TRISB=0X00;
	int *a=(int *) 0x06;
	*a=0xFF;
}
builds without errors, e.g.
Code: 
HI-TECH C Compiler for PIC10/12/16 MCUs (Lite Mode)  V9.83
Copyright (C) 2011 Microchip Technology Inc.
(1273) Omniscient Code Generation not available in Lite mode (warning)

Memory Summary:
    Program space        used    1Bh (    27) of  2000h words   (  0.3%)
    Data space           used     4h (     4) of   160h bytes   (  1.1%)
    EEPROM space         used     0h (     0) of   100h bytes   (  0.0%)
    Configuration bits   used     0h (     0) of     1h word    (  0.0%)
    ID Location space    used     0h (     0) of     4h bytes   (  0.0%)


Running this compiler in PRO mode, with Omniscient Code Generation enabled,
produces code which is typically 40% smaller than in Lite mode.
See http://microchip.htsoft.com/portal/pic_pro for more information.
in fact it should give an error message as variable a is being defined twice (but should not crash MPLAB), try
Code: 
#include <pic.h>

void main(void)
{
	TRISB=0X00;
	int *a=(int *) 0x06;
	*a=0xFF;
}
I note that the compiler that crashes is V9.6 - I am using V9.83
try reinstalling the latest MPLAB and compiler
 
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