i tried to implement tcp on my uC, starting with the handshake to establish the connection (passive open only). And here is my problem: Computer sends the SYN packet, uC replies with SYN,ACK packet, but the computer doesn't answer with an ACK packet. This sounds to me, as if my reply packet is wrong. Possibly my missing checksums (in ip, and tcp layer) are the reason, but i read, checksum 0x0000 would be ok (at least for beta testing). I will post at the end some lines of the ethereal dump.
Does anybody have an idea what could be wrong in my packet (the rfc seems not require special options for connecting...), and what (free) tools (windows) can help me (maybe analysing and finding mistakes and not just showing the packet) to find my fails.
ethereal dump:192.168.101.10 -> 192.168.101.14 port 1111 -> 988 [SYN] seq=5633985 Ack=0 win=8192 Len=0, some options are set 192.168.101.14 -> 192.168.101.10 port 988 -> 1111 [SYN,ACK] seq=4074241 Ack=5633986 win=8192 Len=0, options are all 0x00