Embedded Systems based on Microprocessors and Microcontrollers

Wikipedia defines an embedded system as a “computer system with a dedicated function within a larger mechanical or electrical system, often with real-time computing constraints”. Embedded systems control many devices in common use today. The first embedded systems were based on microprocessors.

A typical system from the 70’s and 80’s:

Modern embedded systems are often based on microcontrollers (i.e. CPUs with integrated memory or peripheral interfaces) but ordinary microprocessors (using external chips for memory and peripheral interface circuits) are also still common, especially in more complex systems. Yet, the trend is to move towards microcontrollers.

From a microprocessor system to a microcontroller

Typical examples of modern Microcontroler Units (MCUs)