Why doesn't my display routine work properly?

[alexan_e]

So when you have a pointer that points to a block of memory, such as an array or a part of an array, you can treat that pointer ``as if'' it were an array, using the convenient notation. In other words, at the beginning of this section when we talked about *ip, *(ip+1), *(ip+2), and *(ip+i), we could have written ip[0], ip[1], ip[2], and ip. As we'll see, this can be quite useful (or at least convenient).

Absolutely not correct.

I have to disagree, this is standard C behavior.
Can you try the following, they work fine for me in keil uvision (ARM version) and copy the content of array1 to array2

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Code C - [expand]
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char my_array1[] = "test";
char my_array2[5];
char *my_char_p;
 
 
int main(void)
{
    my_array2[0] = my_char_p[0];
    my_array2[1] = my_char_p[1];
    my_array2[2] = my_char_p[2];
    my_array2[3] = my_char_p[3];
    my_array2[3] = my_char_p[4];
 
    while(1);
}

---

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Code C - [expand]
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char *my_char_p = "test";
char my_array2[5];
char *my_char_p;
 
 
int main(void)
{
    my_array2[0] = my_char_p[0];
    my_array2[1] = my_char_p[1];
    my_array2[2] = my_char_p[2];
    my_array2[3] = my_char_p[3];
    my_array2[3] = my_char_p[4];
 
    while(1);
}

---

Alex

 

[myru28]

I'm really grateful for your help but nothing you put here seems to work for me...

So I decided to do it in another completely manner but I also get a problem this way, although it's the nearest thing to get it working that I have, in fact I see the problem as even more weird, maybe you can help me with this.

This is the code:

#include <p18cxxx.h>
#include "xlcd.h"
 
 
#pragma config OSC=INTIO67, FCMEN=ON, WDT=OFF, IESO=ON, XINST=OFF, LVP=OFF
 
char XLCD_Disp1[] = "1234567890";
char XLCD_Disp2[] = " PIC_UC       ";
 
 
void main(void)
{
unsigned char config=0xFF,i=0,addr=0,data=0;
ADCON1 = 0xFF;
 
TRISD = 0;
PORTD = 0;	
TRISB = 0;				// Port,pin direction configuration
PORTB = 0;
TRISC = 0;
PORTC = 0;
TRISCbits.TRISC7 = 1;  // make sure this pin is input
TRISE=0;
 
	config = FOUR_BIT  & LINES_5X7;
//********  Configure LCD for four line communication and 5X7 line display *********************************
	OpenXLCD(config);		
		busylcd();		//wait untill LCD controller is busy
 
//*********** Set the starting address in the LCD RAM for display. This determines the location of display ********	
	SetDDRamAddr(0x80);
		busylcd();		//wait untill LCD controller is busy
	putsXLCD(XLCD_Disp1);			//Display string of text
		busylcd();		//wait untill LCD controller is busy
 
//********** Set the address in second line for display ****************************************************		
	SetDDRamAddr(0xC1);
		busylcd();		//wait untill LCD controller is busy
	putsXLCD(XLCD_Disp2);					//Display string of text
		busylcd();		//wait untill LCD controller is busy
	putcXLCD(0x5F);					//dsiplay some chrecter
	 	busylcd();		//wait untill LCD controller is busy
 
	SetDDRamAddr(0x20);
		busylcd();		//wait untill LCD controller is busy
 
	while(1);					//end of program		
 
}

void busylcd(void)
{
	LCDDelay();
	LCDDelay();
	LCDDelay();
}
 
void LCDDelay(void)
{
 
 
int i=0;
for (i=0;i<250;i++);
 
}

But the display just shows on first line "1" and on the second "P", nothing more.

Could you please tell me what might be failing? I don't have an idea and I'm seriously going nuts with this thing, so I'd appreciate it a lot.

Thanks.

 

[Magvitron]

that might be the 1 from the initial string and the P from the next. tery to do it in a loop

 unsigned int i;
     while(dataString[i]!='\0')
	 {
          putsXLCD(XLCD_Disp1[i]);
       	i++;
	}