Re: [lwip-users] LWIP Raw API receive issue

[Sergio R. Caprile]

>> Did youcheck your driver and port are OK
> Yes I have checked that, I am able to receive and transmit without any
> problem if the size is less (approximately less than 100 bytes, could
> be upto 200). As for the driver is concerned I have run the http
> server using this driver, it is able to send upto 512 bytes to the
> client without any problem.

That is not a proof.
You are _SENDING_ 512 but you are receiving "upto" 200, what does that 
mean ??? You have to receive everything you send to the device, be it in 
one or several pbufs, being each pbuf one contiguous block of memory, or 
many (chained).

Are you correctly "traveling" your received pbufs ? They might be 
chained, you can't memcpy(somewhere, p, p->tot_len), you need to go pbuf 
by pbuf copying p->len and checking p->next until you extract tot_len 
bytes; or just use the pbuf handling functions like pbuf_copy_partial()

AFAIK, it is either that or your driver/port is broken.

Being that you are running on bare metal, and you didn't say if you are 
respecting the threading rules, you should have a means for the Ethernet 
controller to say there are frames available, that will a) be remembered 
or b)trigger the extraction of the frame to be put "somewhere" (e.g.: a 
queue).
in the main loop:
In case a) you will call the input which will call the driver and 
extract the frame and give it to lwIP.
In case b) you will extract those frames from "somewhere" and call the 
input to deliver to lwIP.
NO CALLING lwIP LOW-LEVEL FUNCTIONS FROM DIFFERENT CONTEXTS, either all 
main or all interrupt.
Check the wiki and the docs if in doubt.

Being that you are running on bare metal, use your debugger and put a 
breakpoint in those places to see whether you are trashing your data 
before entering lwIP or you need to check your app again.

Unless you have DMA which you did not say, and I cant help you there.