Wierd problem in modifying the bootloader code

Hi,

I am using Phytec LPC3250 board for my design and I have a very important problem that I have been spending time on for days.

I want to modify my bootloader_NOR code so that I can send my application code image from the serial port.

However, when I define a global variable and use this variable in a function it gets wierd values. My code can be simplified as below:

#include "LPC318x.H"

int  m = 0;

void MyFunction(int value)    // do nothing function
{
}

int main(void)
{
  for(;;)
  {
    m++;                        // <- Breakpoint
    MyFunction(m);
  }
}

When I debug the code, I see "m = 0xE0000420" at the breakpoint where I expect to see 0x00.

This ruins all my intention and I cannot proceed to modify the code.

I think the data in the RAM region is corrupted but I dont know why and I have no sensible solution for this.

Thanks for your helps in advance.