Comparaison between Up and Uc

Let's consider in a first time the minimum system to microprocessor

A memory programs (ROM, PROM, EPROM...).
A memory data (RAM).
An interface input / exits (PIA).
A decoder of address
Different buses of interconnection.
-->A system to microprocessor requires a big material place

The microcontrôleurs permits as for them to free these constraints since they integrate in only one circuit at least all resources clean to a minimum system.