[lwip-users] Problems with receiving UDP-checksum fails
From:
ake . forslund
Subject:
[lwip-users] Problems with receiving UDP-checksum fails
Date:
Tue, 14 Jun 2011 10:00:21 +0200
Hello again,
I've started working with the driver
for my ethernet-controller (Microchip ENC424J600) and gotten it to transmit
and receive data using the interface in lwip. I've started to test this
out on DHCP and have thus run into some problems. The DHCP discover-message
is sent and in return an DHCP-offer is sent (and recieved in my platform).
When checking the trace (excerpt below) I'm informed that the UDP-datagram
is discarded due to failing checksum. I've verified the recieved package
with the transmitted data using wireshark and diff and the recieved package
is identical to the sent package.
So my questions are: Where should I
look for the problem? Could it be some endianess- problem? How do I verify
the UDP-checksum calculated by lwip?
Another question: should FCS be stripped
by the low_level_input()-function or should it be saved for the handling
functions?