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TSE_MAC writing extra bits

Altera_Forum
Honored Contributor II
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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?
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Altera_Forum
Honored Contributor II
370 Views

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.

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Altera_Forum
Honored Contributor II
370 Views

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

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