when write to Ethernet Register, I got a reset

Discussion created by lpcware Employee on Jun 15, 2016
Latest reply on Jun 15, 2016 by lpcware
Content originally posted in LPCWare by twicave on Sat Jun 13 00:00:40 MST 2015
I am working on LPC1768's Ethernet function, using LWIP protocol stack.
I have imported the lpcopen project "webserver.uvproj" into my own project.

when I first eliminated all compiler error, and make the project running on my own board.
the code doesn't work.

I traced the init process.found that when executed at:
LPC_EMAC->MAC1 = 2; (through .asm window)
PC pointer then reset to 0x0000;
(I set breakpoint at all exception routine's entry, no exception was captured)

Here is the question:
1.which condition can cause PC pointer reset?

hope someone can help me out.
(I am line by line checking the Initial process now, compared with the original project)