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Altera_Forum's avatar
Altera_Forum
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14 years ago

TSE_MAC writing extra bits

Hello i am mounting some UDP packages inside NIOS2 and sending them via ETH0, however i am getting some malformed packages errors when i take a look at them with Wireshark.

I tried to increase the data and instruction cache to 16/32K but no improvements happened. I am using altera TSE mac at a DE2-115,

When my eth interface sends the packet it always try to complete 32 bits

For exemple

0A 0B 0C 0D

0E 0F

is a valid package

but eth0 is writing

0A 0B 0C 0D

0E 0F 00 00

Any suggestions?

3 Replies

  • Altera_Forum's avatar
    Altera_Forum
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    14 years ago

    Strange, it had to change the alignment. The alignment is probably can be done in TCP/IP stack. Check that too.

  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    14 years ago

    Ok but why the ping doesnt align the data?

    When i ping with my DE2-115 everything is ok at the wireshark and it isnt aligned.

    I also disabled the option to align at the MAC but nothing changed.
  • Altera_Forum's avatar
    Altera_Forum
    Icon for Honored Contributor rankHonored Contributor
    14 years ago

    The MAC has an option to align data to 32bit boundary, so add 16 bits of any data in the begining of the data OR disable that option.