I have a machine with the OS burned in ROM (BBC Micro). I can use and EEPROM and write my own if I want to. I can also switch between ROMs to boot from - I hav

I have a machine with the OS burned in ROM (BBC Micro). I can use and EEPROM and write my own if I want to. I can also switch between ROMs to boot from - I have BBC Basic, Word*, Publisher, Forth. It was a great idea when you only have 32K RAM. The ROMs are page mapped in.