Sorry for the mistake I made in the text. The IP address of the DSP and PC are different(10.110.41.56/10.110.41.57). I have connected the DSP and PC directly through RJ45 socket via a net cable. When I send data from the DSP to PC via UDP, I can see those data on Wireshark. I have not embedded ICMP protocol in DSP yet. However, I wonder the Wireshark thing somehow validates the connectivity of the DSP and PC.
Thank you, guys, the problem has been solved. It was the IP checksum that caused the problem. Wireshark does not validate the IP checksum check under default mode. Therefore, I did not manage to notice the wrong byte order of the IP checksum. Now everything seems to be working fine. Anyway, thank you guys for your kindly help!