Hi, On Thu, Nov 02, 2017 at 05:02:36PM +0000, Raivis wrote: > That's a very good, point, I've been so frustrated that it didn't occur to > me that I can just print the packet in my serial function. > > Apologies I somehow over glanced your suggestion before. > > I enabled the PPP_DEBUG and PRINTPKT_SUPPORT, and removed all filters from > ppp_dump_packet() in utils.c, leaving just "pp_dbglog()" function call. > > > From my inexperienced point of view, the PPP side seems to work fine I > guess.
It is, pppos_netif_output() is the last step in the lwIP PPP stack, it means (if it succeed, which is the case here), that your serial output callback was called. > Is it something to do with netif? I don't understand to which scope this question apply; The netif is properly configured for me, we can undoubtfuly see the TCP SYN attempt in the debug log, meaning the packet goes down all the stack up to your serial low level writer. If you are talking about your low level flow serial driver, it looks fine from here, you already said you saw the TCP packet properly sent on wire. However, there might be some missing dark magic in your dialup chatscript ("AT" commands) before starting the PPP session. Your modem accepts the PPP session and set a apparently usable IP address so it should work but, well, some of these modems (all?), especially cellular ones, have some quirks[*] in their firmwares. [*] I'm saving a strong word here Maybe you could try with UDP first instead of TCP; I don't think it would help in this case but we never know. Sylvain
signature.asc
Description: Digital signature
_______________________________________________ lwip-users mailing list lwip-users@nongnu.org https://lists.nongnu.org/mailman/listinfo/lwip-users