Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

Problem SDRAM....Burst Terminate!!!

Hi all, Ok, I found out that SDRAM keeps writing forever and never stop, when I call IOWR_32DIRECT(...) in SignalTap. When I look at Dev Board Cyclone II and it does show Write and Bur...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

Thanks spaugh and BadOmen.

Even I tried (sys_clk=25mhz and sdram_clk=33mhz), I still couldn't get it working.

In my Nios

unsigned int i, w, r;

for (i=5; i<8; i++)

{

IOWR_32DIRECT(SDRAM_BASE, i, i);

usleep(20);

}

for (i=5; i<8; i++)

r = IORD_32DIRECT(SDRAM_BASE, i);

I see in signaltap...

write 5 .... wait (20)

write 6 .... wait (20)

write 7 .... wait (20) ... So I think the write method seems working right.

But when I read 5, 6, 7... I got 0, but I do see (CS, RAS, CAS, WE) L H L H on the lines.

Thanks,

Sean