Honored Contributor
Honored Contributor
background: i have 3 altera de2 evaluation boards.
two of these boards have difficulty receiving packets with the same program loaded (de2_net demo program). the first byte received (rx_len[0], supposedly the length of the packet) is consistently wrong (i have seen three values: 1, 400, and 800, all of which should have been udp packets of length 45 bytes, data portion 3 bytes). if i continue to read in the other bytes of the packet, they are all wrong as well, and the number of them (that are not read in as 0) is incorrect.
an unrelated problem, which would work well enough for me: i have been working with one board consistently for about three months now (one of the two that does not receive packets properly), and now my program will only load onto this board (the other two give the generic "verify target address failed between 0x20 and 0xffff"). the three boards were ordered and received at the same time, about ten months ago, and i made sure to regenerate the system from the sopc builder and recompile on each: the sof file is created and downloaded properly, but the program will not download from the nios ii ide.
i am somewhat short on time to correct these issues, and would appreciate any advice given, including work-arounds.
<div align='right'><{post_snapback}> (index.php?act=findpost&pid=22712)
--- quote end ---
--- Quote End --- issue solved. apparently 120 MHz is pretty close to max clock speed for the SDRAM, and the boards all have slightly different profiles. as for the ethernet controller working sporadically, that's also a speed problem (works fine at 50 MHz), but i'll put that up in a different post.
