ROM Mode

ROM mode was added to the Green Hills simulators to facilitate creation of embedded programs for real-time systems. The MCore simulator in ROM mode will not simulate various system calls available in OS simulation mode. Instead, only the minimum hardware is simulated, such as the CPU and memory systems.

In ROM mode the executable is loaded into simulator memory using the physical addresses specified in the object file instead of virtual addresses. Then execution begins at the address stored in the vector table (0x0), as if the CPU were just turned on. Thus, the object file acts like programmable ROM where your system code can reside.

Other features of ROM mode:

ROM mode is useful for writing and testing exception handlers and parts of an operating system. Also, you will have to write at least some start-up code in pure assembly language since this mode gives you such a bare-bones processor.


Previous

Next



Copyright © 1999, Green Hills Software. All rights reserved.