Question

A microcontroller differs from a microprocessor in that it has

• A. on-chip memory and on-chip ports
• B. only on-chip memory but not on-chip ports
• C. only on-chip ports but not on-chip memory
• D. neither on-chip memory nor on-chip ports

Hint:

Microcontroller = CPU + Memory + I/O on a single chip.

Answer 1

The Correct Option is A

Step 1: Think of a microprocessor as just the brain.
A microprocessor by itself is only the central processing unit. To actually build a working system with it, a designer has to add separate external chips for RAM, ROM, and input or output ports, then wire them all together on a circuit board.
Step 2: A microcontroller is a complete tiny computer on one chip.
A microcontroller takes that same CPU and packages it together with its own memory and its own I/O ports inside a single integrated circuit, so it is often called a system on a chip.
Step 3: See what this means in practice.
Because everything needed to control a device is already built in, a microcontroller can be dropped straight into an embedded application with very little extra circuitry, unlike a bare microprocessor.
\[ \boxed{\text{on-chip memory and on-chip ports}} \]