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Re: TCP/IP large packets -errors


On Fri, Apr 20, 2001 at 02:33:23PM +0200, Marek Łącki wrote:
> I have a problem with stack TCP or network card driver (NE200) on platform
> i386.
> Stack works correctly if i send packets less than 1500 bytes. When I   send
> more than 1500 bytes for example 1600 bytes ( tested on ping ),  eCos
> responses for first part (1500 bytes) and dosen't response for next
> parts(100bytes). Then if i send later less  than 1500 bytes ,eCos response
> for request and send extra this 100 bytes from first large frame.
> What's happend ?????

This works correctly on an EBSA with a i82559. I can ping with big packets,
eg 

ping -s 1600 192.168.9.215 

and both fragments are sent imeadiatly. My guess there is a bug in the
NE2000 device driver. There may be a race condition when two frames
are sent in quick sucsession. eg, its adding the second frame into the
TX queue while the TX complete interrupt for the previous frame goes
off. The second frame is then not sent until the next frame is queued
to be sent and so kicks the delayed frame out.

        Andrew


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