Traditional computer CPUs was designed with components on various boards. With IC technology, it became possible to build the CPU on a single chip. A microprocessor is a CPU that happens to be on a single chip.
A computer with a microprocessor as a CPU is known as a microcomputer. A microcontroller is an entire computer on a single chip (MPU + Memory + I/O Interfacing circuits).
The key difference between a microprocessor and a microcontroller is described in the following table.
| Microprocessor | Microcontroller |
|---|---|
| Consists of only a Central Processing Unit. | Contains a CPU, Memory, I/O all integrated into one chip. |
| It is mainly used in personal computers. | It is used mainly in embedded systems. |
| Microprocessor is complicated and expensive,with a large number of instructions to process. | Microcontroller is inexpensive and straightforward with fewer instructions to process. |
| It has no RAM, ROM, Input-Output units, timers, and other peripherals on the chip. | It has a CPU along with RAM, ROM, and other peripherals embedded on a single chip. |
| It uses an external bus to interface to RAM, ROM, and other peripherals. | Microcontroller uses an internal controlling bus. |
| It’s used for general purpose applications that allow you to handle loads of data. | It’s used for application-specific systems. |