Re: [avr-gcc-list] Bizarre string problem, part 3

[gouy yann]

Hi,

both Richard and Ian are right.

I've been running your code, compiled with the
makefile provided with WinAVR, on simulavr and it runs
perfectly well.

both your compilation and your objcopy are the
problem.

regards.

    Yann


 --- Ian Caddy <address@hidden> a écrit : 
> I actually didn't notice the compilation and
> downloading commands in 
> your original message.
> 
> Following on from my other email, you can not just
> use the .text section 
> in the obj-copy to get your hex file as this will
> not contain the 
> initialisation data I was talking about.
> 
> Try the objcopy command without the "-j .text"
> option and see how you 
> go, although you also don't seem to have linked with
> the libraries that 
> you will need to perform the initialisation as well.
> 
> I would get the example makefile that comes with
> WinAVR (for example) 
> and use it to generate your compilation and linking.
> 
> regards,
> 
> Ian Caddy
> 
> 
> André - BOL wrote:
> 
> > Hi!  
> >  
> > First, I'd like to thank everybody for the tips,
> but they haven't
> > worked. I formulated a new very simple example to
> demonstrate the
> > problem I'm facing.
> >  
> > Suppose I "initialize" a variable in some
> different and equivalent ways:
> >     char a[10]  = {'T', 'T', 'T', 'T', 'T' };    
> >     char b[]      = "TTTTTTT";
> >     char c[10];      c[0]='T';    c[1]='T';    
> c[2]='T';      c[3]='T';
> > //i think this can't be called an
> initialization!!!
> >     char *d      = "TTTTTTT"
> >     
> >     now, I perform the test
> >         
> >     if ( x[2] == 'T' ) printf("hi");    // x = a,
> b, c or d
> >  
> >     All examples are LEGAL STANDARD PURE C. I
> chose size 10 and the 3rd
> > ( [2] ! ) element to avoid avoid any doubts that I
> had enougth space
> > reserved, and that I took the correct character.
> All tests should return
> > true and print "hi". My example ttest.c is to be
> run on Pc and shows
> > exactly that with printf's
> >  
> >     PROBLEM: when using the very same code on the
> ATMEGA, changing the
> > printf's for "turn on led 1", "turn on led 2",
> etc., only the third char
> > sequence (C) causes correct evaluation of the if
> expression (i can see
> > that, because I have the leds correctly connected
> and only the 3rd one
> > lights)
> >  
> >     I tryed this under WINDOWS AND UNDER LINUX,
> using avr-gcc. 
> >  
> >     Compilation and downloading commands:
> >  
> > avr-gcc -g -mmcu=atmega32 -Wall -o t.o t.c 
> > avr-objcopy -j .text -O ihex t.o t.hex
> > uisp -dprog=dapa --erase
> > uisp -dprog=dapa --upload if=t.hex -dno-poll -v=3
> --hash=32
> >  
> > 
> > 
> >
>
------------------------------------------------------------------------
> > 
> > #include <avr/io.h>
> > #include <string.h>
> > 
> > 
> > void xisa() {
> >     // doesn't work
> >     char aux[10] = {'A', 'A', 'A', 'A', 'A'} ;
> >     if ('A' == aux[2]) PORTB |= 0X01;   // 1st led
> > }
> > 
> > 
> > void xisb() {
> >     // doesn't work
> >     char aux[] = "BBBBBBB"; 
> >     if ('B' == aux[2]) PORTB |= 0X02;   // 2nd led
> > }
> > 
> > void xisc() {
> >     // WORKS !!!!
> >     char aux[10];
> >     
> >     aux[0] = 'C';
> >     aux[1] = 'C';
> >     aux[2] = 'C';
> >     aux[3] = 'C';
> >     aux[4] = 'C';   
> >     aux[0] = '\0';
> >     
> >     if ('C' == aux[2]) PORTB |= 0X04; // 3rd led
> > }
> > 
> > 
> > void xisd() {
> >     // doesn't work
> >     char aux[10];
> >     aux[0] = '\0';
> >     strcat(aux, "DDDDDDDD");
> >     if ('D' == aux[2]) PORTB |= 0X08;   //4th led
> > }
> > 
> > 
> > 
> > void main(){
> > 
> /***************************************************
> >     *  I/O
> > 
> ***************************************************/
> >     outp(0xff,DDRB);   // PORT B = OUTPUT   
> >     outp(0xff,PORTB);  // WRITE PORT        
> >     PORTB = 0x00;      // BLANKS PORT
> >             
> >     // TRY EACH OF THESE COMMANDS ALONE, 
> >     // and the problem persists
> >     xisa();  
> >     xisb();
> >     xisc();
> >     xisd();
> >     
> >     
> >     
> > }
> > 
> > 
> > 
> >
>
------------------------------------------------------------------------
> > 
> > #include <string.h>
> > #include <stdio.h>
> > 
> > 
> > void xisa() {
> >     // doesn't work
> >     char aux[10] = {'A', 'A', 'A', 'A', 'A'} ;
> >     if ('A' == aux[2]) printf("\n1st led"); 
> > }
> > 
> > 
> > void xisb() {
> >     // doesn't work
> >     char aux[] = "BBBBBBB"; 
> >     if ('B' == aux[2]) printf("\n2ndt led"); // 2nd
> led
> > }
> > 
> > void xisc() {
> >     // WORKS !!!!
> >     char aux[10];
> >     
> >     aux[0] = 'C';
> >     aux[1] = 'C';
> >     aux[2] = 'C';
> >     aux[3] = 'C';
> >     aux[4] = 'C';   
> >     aux[0] = '\0';
> >     
> >     if ('C' == aux[2]) printf("\n3rd led"); // 3rd
> led
> > }
> > 
> > 
> > void xisd() {
> >     // doesn't work
> >     char aux[10];
> >     aux[0] = '\0';
> >     strcat(aux, "DDDDDDDD");
> >     if ('D' == aux[2]) printf("\n4th led");  //4th
> led
> > }
> > 
> > 
> > 
> > void main(){
> > 
> /***************************************************
> 
=== message truncated === 

=====



        

        
                
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