W5500 vs. W5100 / W5200

Question

Hello, I noted a different behaviour between W5500 and W5100 responding to [SYN] packet when all sockets are busy and no more connections can be accepted. While W5100 answer with a [RST] packet, W5500 send a [RST,ACK] packet, I presume to speed up the ethernet traffic. This difference impacts on browsers behaviour: with W5100 there is a retransmission of the [SYN] packet and the request is acknowledged as soon a socket becomes available with W5500 the request is aborted Is there a way to set W5500 in order to send only the [RST] packet without the ACK as W5100 does? I haven’t a W5200 to test. Does anybody knows how W5200 behaves? Thanks Best regards E.M.Villa

hjjeon0608 · Answer

Hi, W5100 is implemented to send RST packet. W5200/W5500 are implemented to send RST/ACK packet. It is designed as hardware not software, so it cannot be changed unfortunately.

emvilla · Answer

Hi hjjeon, thanks for your answer. Since we are tuning our project in these days and we want to use Wiznet, I think we will probably use W5100. Could you tell me please if W5100 is a valid choice for new projects? Or it will be discontinued soon? Thank you very much. Regards E.M.Villa

hjjeon0608 · Answer

Hi, W5100 is in Arduino official ethernet shield and we don’t have plan to discontinue. But W5500 is more cheap, better performance and have 8 sockets. So, W5500 is more suitable for web server. But if RST packet is critical issue, maybe W5100 is good choice.