read/write in bram block

Hi all,
 i am designing a system in which we have a bram block,microblaze
processor and other essential component.
 i have written a verilog code for bram controller (successfully
compiled)to interface bram block to opb bus.now i have to write a c
code to perform read write operation in bram block.i have written
following code


 #include <stdio.h>
#include <mb_interface.h>
#include <xutil.h>
int main(){
printf("Hello this is the start, printing using print\n");
 volatile char *pointer = ( volatile char *) 0x10013405;
  *pointer = 'c';
char temp = *pointer;
printf("%c %c\n",temp , *pointer);
return 0 ;
}

which is not working
so regarding this i have following question
1-in c ,is it possible to assign address to a pointer according to
us ????
2-is it necessary to use gpio function to read write operation in a
peripheral ??


if you find some conceptual mistake in code then please reply

with regards
 Ajay

> Hi all,
> i am designing a system in which we have a bram block,microblaze
> processor and other essential component.
> i have written a verilog code for bram controller (successfully
> compiled)to interface bram block to opb bus.now i have to write a c
> code to perform read write operation in bram block.i have written
> following code
> 
> #include <stdio.h>
> #include <mb_interface.h>
> #include <xutil.h>
> int main(){
> printf("Hello this is the start, printing using print\n");
> volatile char *pointer = ( volatile char *) 0x10013405;

You shouldn't need a cast here and both volatile keywords add nothing additional 
in this context and could hide errors.
You should also look into xil_printf()'s.

> *pointer = 'c';
> char temp = *pointer;
> printf("%c %c\n",temp , *pointer);
> return 0 ;
> }
> which is not working

But, you never said what the output of the printf() actually was.

> so regarding this i have following question
> 1-in c ,is it possible to assign address to a pointer according to
> us ????

Yes, it's valid but not because of C, but because you are using a flat non-managed 
memory model.  Try this kind of shenanigans in Windows and you most likely 
will get a SEG Fault.

> 2-is it necessary to use gpio function to read write operation in a
> peripheral ??

You could write your own.

> if you find some conceptual mistake in code then please reply
> 
> with regards
> Ajay

On Jul 4, 12:23 pm, rajiv...@gmail.com wrote:
> Hi all,
>  i am designing a system in which we have a bram block,microblaze
> processor and other essential component.
>  i have written a verilog code for bram controller (successfully
> compiled)to interface bram block to opb bus.now i have to write a c
> code to perform read write operation in bram block.i have written
> following code
>
>  #include <stdio.h>
> #include <mb_interface.h>
> #include <xutil.h>
> int main(){
> printf("Hello this is the start, printing using print\n");
>  volatile char *pointer = ( volatile char *) 0x10013405;
>   *pointer = 'c';
> char temp = *pointer;
> printf("%c %c\n",temp , *pointer);
> return 0 ;
>
> }
>
> which is not working
> so regarding this i have following question
> 1-in c ,is it possible to assign address to a pointer according to
> us ????
> 2-is it necessary to use gpio function to read write operation in a
> peripheral ??
>
> if you find some conceptual mistake in code then please reply
>
> with regards
>  Ajay

Could it be the IP core you wrote? Why write custom BRAM interface
controller when one already comes with EDK (opb_bram_if_cntlr)?
Alternatively, if you have no other masters that need access to the
BRAM other than the Microblaze, you might want to consider interfacing
via the LMB through the lmb_bram_if_cntlr. This approach has better
performance since the single-master nature of the LMB requires no
arbitration.