I'm trying to implement an SNTP client based on the example that comes with lwIP 1.4.x but with no success. That's what I have done:
- I have rewritten the example a bit to get rid of the sys_xxx() functions which are not available for me
- I do a ntohl() on all IP's that are retruned by ipaddr_aton(), this seems to be necessary on my platform (at least for configuring the IP of my Ethernet interface it has to be done to apply the correct address for it, so I assume this is necessary for all IPs)
- based on this I do a ntohs() for the SNTP-port too
- I have set IP, gateway and netmask for my Ethernet interface correctly
- NTP-server-IP is correct too
- receive-callback for UDP-responses is available and valid
- udp_sendto() that transmits the SNTP UDP request returns with ERR_OK
- firewall is open for NTP-responses, this works fine for all other systems in same network
Nevertheless my receive-callback is never called, I do not get back a response from the NTP-server.
So...any ideas what could be wrong/where I could look what is going on?