As DMA read / write to RAM on background and cache is not updated which occurs when DMA and cache is used together ,so when I use the Ethernet model which has DMA , I choose a part of RAM memory which is not be cached.
This way is asked by technical support when I bring up relate question last time.the address below is the answer.
It is really helpful and I have used it . "myram" in the photo is the RAM memory which I used for Ethernet.
But recently I need to modify the memory, I make a little modify about lcf, but I reserve the part of RAM memory about Ethernet.
But I do not know why the Ethernet is not make effect after I modify it while other is running well .It has puzzled me for two weeks .I really hope I can get help from someone. If the information is not enough, please contact me.