To understand the difference between microprocessor and microcontroller we need to understand what microcomputer system and microcontroller (i.e. single-chip microcomputer system) are.
To make a complete microcomputer system, only a microprocessor is not sufficient. It is necessary to add other peripherals such as read-only memory(ROM), read/write memory(RAM), decoders, drivers, number of input/output devices to make a complete microcomputer system.
In addition,special-purpose devices, such as interrupt controllers, programmable timers, programmable I/O devices, DMA controllers may be added to improve the capability and performance, and flexibility of a microcomputer system.
The key feature of a microprocessor-based computer system is that it is possible to design a system with great flexibility. It is possible to configure a system as a large system or a small system by adding suitable peripherals.
On the other hand, the microcontroller incorporates all the features that are found in the microprocessor. However, it has also added features to make a complete microcomputer system on its own. The microcontroller has built-in ROM, RAM, parallel I/O, serial I/O, counters, and a clock circuit. The microcontroller has on-chip (built-in) peripheral devices. These on-chip peripherals make it possible to have a single-chip microcomputer system. (see figure 1 and figure 2 below)
There are a few more advantages of built-in peripherals:
- Built-in peripherals have smaller access times hence speed is more.
- Hardware reduces due to single on-chip microcomputer system.
- Less hardware reduces PCB size and increases reliability of the system.
Author of this post
This post is co-authored by Professor Saraswati Saha, who is an assistant professor at RCCIIT, a renowned degree engineering college in India. Professor Saha teaches subjects related to digital electronics & microprocessors.
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