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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

    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.

  • Altera_Forum's avatar
    Altera_Forum
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    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

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