ucontroller and uMicroprocessor

Thread Starter


Joined May 26, 2004
What is the difference between a Microcontroller and a Microprocessor. I get confused from many definitions of a Microcontroller because it is often referred to as a type of process/microprocessor. From my understanding, the difference is that a Microcontroller is usually designed to perform one or a few specific tasks and has RAM and/or ROM associated with it while a Microprocessor handles many tasks and is made of three parts: ALU, Control Unit, and Registers. I am right?


Joined Feb 24, 2006
In my experience a microcontroller is a single chip device without an external address and data bus. The manufacturer of microcontrollers must proliferate them in endless varieties of packages and prices with different sets of peripheral devices.

A microprocessor has an external address and data bus. On these external busses must go the RAM, Flash, and peripheral devices like UARTS, Timers, Ports and so forth. Here the manufacturer makes a small number of processors and some peripheral devices. Generally more flexible if the desired peripherals are available, but also more costly.

In many respects it is a distinction without a difference. The firmware absolutely cannot tell the difference, and the number of tasks has nothing to do with anything IMHO.


Joined Jul 22, 2007
A microcontroller is more of a single chip computer, contains everything needed.
A microprocessor, is just that, the processing unit. You need to provide a whole lot of additional circuity in order to get some sort of function out of it.

The microcontroller has a microprocessor built into it, along with memory, I/O drivers, comunications. Plus, you get some device features that make it handy to interface with your projects.