Hi, I made the following setup. But my fifo write is working fine but fifo read is not working fine. Here is sample output
62
Please enter a number:
45
you entered the value :45
root@socfpga_cyclone5:~# ./customfifoloopback4write
Please enter a number:
46
you entered the value :46
root@socfpga_cyclone5:~# ./customfifoloopback4write
Please enter a number:
47
you entered the value :47
root@socfpga_cyclone5:~# ./customfifoloopback4write
Please enter a number:
48
you entered the value :48
root@socfpga_cyclone5:~# ./customfifoloopback4write
Please enter a number:
49
you entered the value :49
root@socfpga_cyclone5:~# ./customfifoloopback4write
Please enter a number:
60
you entered the value :60
root@socfpga_cyclone5:~# ./customfifoloopback4write
Please enter a number:
61
you entered the value :61
root@socfpga_cyclone5:~# ./customfifoloopback4write
Please enter a number:
62
Now when I read back data it is like just one number while I want to read out whole of the fifo
////////////////////////////
the output value from the fifo is 62
/////////////////////////////
////////////////////////////
the output value from the fifo is 62
/////////////////////////////
////////////////////////////
the output value from the fifo is 62
/////////////////////////////
////////////////////////////
the output value from the fifo is 62
/////////////////////////////
////////////////////////////
the output value from the fifo is 62
/////////////////////////////
////////////////////////////
the output value from the fifo is 62
/////////////////////////////
////////////////////////////
the output value from the fifo is 62
/////////////////////////////
////////////////////////////
the output value from the fifo is 62
Here is c code for read and write
#define REG_BASE 0xFF200000
#define REG_SPAN 1024
void* virtual_base;
volatile unsigned int * FIFO_write_ptr;
unsigned int value;
int main ()
{
int fd = EXIT_FAILURE;
fd=open("/dev/mem",(O_RDWR|O_SYNC));
if (fd < 0) {
perror("open");
exit(EXIT_FAILURE);
}
virtual_base=mmap(NULL,REG_SPAN,(PROT_READ|PROT_WRITE),MAP_SHARED,fd,REG_BASE);
if (virtual_base == MAP_FAILED) {
perror("mmap");
}
FIFO_write_ptr=(unsigned int *)(virtual_base+FIFO_0_IN_BASE);
printf("Please enter a number: \n");
scanf("%i",&value);
*FIFO_write_ptr=value;
printf("you entered the value :%i\n",*FIFO_write_ptr);
return 0;
}#define REG_BASE 0xFF200000
#define REG_SPAN 1024
void* virtual_base;
volatile unsigned int * FIFO_read_ptr;
int i;
int main ()
{
int fd = EXIT_FAILURE;
fd=open("/dev/mem",(O_RDWR|O_SYNC));
if (fd < 0) {
perror("open");
exit(EXIT_FAILURE);
}
virtual_base=mmap(NULL,REG_SPAN,(PROT_READ|PROT_WRITE),MAP_SHARED,fd,REG_BASE);
if (virtual_base == MAP_FAILED) {
perror("mmap");
}
FIFO_read_ptr=(unsigned int *)(virtual_base+FIFO_0_OUT_BASE);
for(i=0;i<8;i++)
{
//reading data from the fifo
printf("////////////////////////////\n");
printf("the output value from the fifo is %d\n",*FIFO_read_ptr);
printf("/////////////////////////////\n");
}
return 0;
}
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