hang up after call ROM_FlashErase(0xF0000), chip TM4C129ENCPDT

Hi~All

I meet an issue that after I call ROM_FlashErase (0xF0000), my firmware sometimes hangs up, but if I only call ROM_FlashErase (0x1C000) and mark ROM_FlashErase (0xF0000), it always works fine.

How do I solve this issue? Thanks :-)

Chip: TM4C129ENCPDT

My code is like the following

void my function {

    ROM_FlashErase (0xC000);

    ROM_FlashProgram (0x1234, 0xC000,4);

    ROM_FlashErase (0x1C000);

    ROM_FlashProgram (0x1234, 0x1C000,4);

    ROM_FlashErase (0xF0000);// <---Mark this line and then it always works fine.

    ROM_FlashProgram (0x1234, 0xF0000,4);

}