Re: [lwip-users] HOWTO LwIP if NO_SYS = 1

[address@hidden]

Niraj Kulkarni wrote:
> In continuation with pervious questions, I have few more
>
> 1.      What is the significance of "ram" variable in mem_init().
>          I am referring : LwIP_M16C (although it is for uCos OS and my system 
> is NO OS),
>          here "ram" is a well array defined by user of size MEM_SIZE
>          In lwip-1.4.0.rc2 source code : "ram" is a static u8_t pointer.
>
>          I guess MEM_SIZE is the maximum heap memory (or say buffer ) lwip will 
> use and I have to configure
>          "memp" and "pbuf_pool" considering MEM_SIZE in mind.
>
>          Should I assign my controllers RAM memory to this "ram" variable?
No, just define MEM_SIZE and the compiler will allocate memory for you. 
But make sure your compiler/linker warns if you allocate too much memory 
for your target controller
> 2.      As I will be using NO_SYS = 1 , in a single-threaded (non-OS) 
> environment,
>          What will be my "input_function" in netif_add : ip_input() or 
> tcpip_input() ?
When using an ethernet device, ethernet_input() will be the correct 
function. tcpip_input() will not even be compiled for NO_SYS==1.
>          Ref: http://www.sics.se/~adam/lwip/os.html
That one is so old. It can be used as a starter, but not as an 
up-to-date reference: since Adam wrote this, many things have changed in 
the stack.

Simon