[Top][All Lists]
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
Re: [lwip-users] problems and solutions (?)
From: |
Chris WIlliams |
Subject: |
Re: [lwip-users] problems and solutions (?) |
Date: |
Wed, 11 Aug 2004 20:05:43 +0100 |
In message , address@hidden writes
>Subject: Re: [lwip-users] problems and solutions (?)
>To: "Mailing list for lwIP users" <address@hidden>
>Message-ID: <address@hidden>
>Content-Type: text/plain; charset="iso-8859-1"
>
>Hi Kieran,
>
>I'll follow your suggestion to inform you about problems I encountered. I'm
>working on a XC161-Board with CS8900a using GNU-C (from Hightec). I tried to
>build an easy webserver application using the minimal unix 'echo server'
>application as an example how to use the raw api.
>
>It didn't work. Not even the TCP SYN frame from the browser of my PC had
>been answered by lwip. The reason for this was that a call to pbuf_header()
>from etharp_output() failed because there was not enough space allocated for
>the pbuf to hold the link layer header.
>
>I was able to fix this by changing the definition of PBUF_LINK_HLEN (which
>was set to 0 !?) in opt.h to the actual size of 14 for the link layer
>header. Afterwards everything seemed to work quite well.
>
>Are there any applications or drivers where a definition of
>
>#define PBUF_LINK_HLEN 0
>
>makes any sense?
>
>Uwe
I have a file lwipopts.h with the definition:
/* PBUF_LINK_HLEN: the number of bytes that should be allocated for a
link level header. */
#define PBUF_LINK_HLEN 16
This is overriding the value of 0 quoted above so my system works.
Can anyone explain why I have an override of 16 and could I change it to
14?
Thanks, Chris.
--
---------------------------------------------------------------------------
| Chris Williams EMail address@hidden |
| Tel/Fax 01686 688065 |
| Chrysalis Design. Electronics, Computers, Hardware, Software. |
| Design and development to meet all your needs. |
---------------------------------------------------------------------------
[Prev in Thread] |
Current Thread |
[Next in Thread] |
- Re: [lwip-users] problems and solutions (?),
Chris WIlliams <=