I am planning to use the P89C51RD2 chip and have loader code to load from an EEPROM update wand. I am planning to base the loader in one module of the flash and base the rest of the code, code that can be updated, in the other sections. To ensure this works I think I need the main section of the loadable code and the interrupts need to be fixed in code memory to ensure operation after reloading code. Can anybody see a problem with this?