There was nothing special about NES’s architecture. It was literally just a cart that, when plugged in, was directly wired to a subset of address lines. Utilizi

There was nothing special about NES’s architecture. It was literally just a cart that, when plugged in, was directly wired to a subset of address lines. Utilizing the CHR/PRG separation allowed for some interesting mapper designs and eased graphics loading, sure. But the Master System was as capable of mapping cart based logic. The Master System just didn’t need it during its peak sales period (due to the aforementioned more capable base design) nor did it last long enough for developers to focus on developing anything special (Nintendo and a few major companies make up the developers of the majority of “official” mappers, Sega didn’t have many big names at the time nor did the support the system long enough to need it). That being said, there totally were a few mappers developed for the console [1]. 1 - https://www.smspower.org/Development/Mappers https://www.smspower.org/Development/Mappers