I am using W5500 as a FTP client. I have tested it with an internal FTP server (within intranet) and an external free FTP server (via internet) successfully. But when I test it with my customer’s FTP server, it always fail with the returned values of SOCKERR_TIMEOUT or SOCKERR_SOCKCLOSED when connect() is called. I do not see any TCP packets sent out by W5500 with Wireshark.
All three FTP servers can be access successfully by FileZilla on PC. The only difference of my customer’s FTP server I can tell is that I cannot ping it.
I have also checked the registers IR, SR, MR, IMR and find nothing strange. Could anyone drop me some hints what I should check in the next step?
Many thanks in advance!