Problem about DM9000A and NicheStack....

Hi,

Can you help me,

1.

When I'm using NicheStack(DM9000A as NIC),I met some strange problems:

when i'm debugging TCP prot,the program entered ip_output() function.It triggered a panic(),and told me this message:

ip_output: overflow

The program crashed after this message...

How to avoid this ?

2.

The bit[0] of DM9000A's TX Control Register (TCR) sometimes don't clear itself after sending completely. I wrote:

while(ior(TCR)&0x01)

{

udelay(5);

}

and the program stuck here....

What should I do?

Thank you