[lwip-users] Mapping pbuf to Buffer Descriptor on MPC582T

[Muhamad Ikhwan Ismail]

 
Hi guys,
 
I am porting lwip1.2.0(not using CVS for updates) to MPC852t with a commercial RTOS from MQX
I am a beginner in lwip.
Got 2 qs on a problem I am having.
 
1. MPC852T has a dual port ram with buffer descriptors, which have pointers to the buffer/frame to be sent
    and the Ethernet controller automatically fetch the pointed data for transmission as soon as I set a flag up.
    The problem lies on the fact that the first-in-chain  pbuf payload pointer points to the actual data and skipped the headers, 
    or at least that is the way  I understood it from the manual. I have setup an array of the same amount of buffer descriptors for
    each packet. How do I force the payload pointer of the first-in-chain pbuf to point to the start of the ethernet header
    so that I can assign this to the first buffer descriptor data pointer ?
 
2.  Can someone show me how do I initialise the lwip stack to be used with the sockets API (maybe the flow)? And is the usage of the
     sockets api allows the lwip to be multithreading able ?
 
Im sorry for the beginner's question and would appreciate it if anyone could help me out or at least advice me on how to tackle
the 2 things i have in mind.
 
Thanks a lot
M. Ikhwan Ismail  
   
 

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