The Emulators

Most emulators do not emulate the main system bus; each input and output device is often treated as a special case. Most usually follow the following basic infrastructure scheme:

Handling switches or through procedures that set flags readable by the CPU simulator whenever a switch is raised, allowing the virtual CPU to convert the virtual switches.

Writing to and reading from physical memory, by means of two similar procedures while dealing with logical memory (contrary to the latter, the former can commonly be bypassed, and direct references to the memory array are employed instead).

Emulators boot via ROMS which are nothing more or less than the contents of the cartridges, floppy disks or tapes that were used with older systems. Physically on PCs, ROMS are binary files that can be loaded into memory.

At this point we can explain a simile so that you can understand all the jargon that has been discussed in the previous paragraphs. The emulator is a program that performs the functions of a console or computer (e.g. Super Nintendo), while the ROMS act as a cartridge, CDROM or tape (e.g. Castlevania), so if we have the emulator and the ROM we could play our Super Nintendo as if we had it plugged in the room or the living room, simple, fast and reliable.