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FreeRTOS + tcp Frame Check Sequence

Posted by friesen on June 11, 2018

I am using FreeRTOS + TCP.

Either I have something misconfigured, or there is some mishandling of a 64 byte minimum ack packet.

Wireshark flags tcp acks and fin, acks as having a Frame check sequence error. I think this is due to sending 0's for the last 4 bytes. I think that a FCS packet is minimum 64, and a non FCS is 60 perhaps? I can't find anything so far in the configuration that targets this issue.

FreeRTOS + tcp Frame Check Sequence

Posted by friesen on June 11, 2018

This post can be ignored, the ATWILC1000 is apparently padding these bytes internally.

FreeRTOS + tcp Frame Check Sequence

Posted by heinbali01 on June 11, 2018

In the sample projects, you will often find:




The padded bytes will all be zero.

Several EMAC's ( like, apparently ATWILC1000 ), are able to padd bytes as well. In that case, you can keep ipconfigETHERNET_MINIMUM_PACKET_BYTES undefined.

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