Introduction to Microcontrollers

Question 1

What is a microcontroller?

Answer 1

A compact computer system on a single chip containing a CPU, memory, and peripherals for embedded applications.

Question 2

What is an embedded system?

Answer 2

A hardware and software system designed to perform one dedicated task under constraints like power, speed, and reliability.

Question 3

Give examples of microcontroller uses.

Answer 3

Appliances, cars, robotics, sensors, smart devices.

Question 4

Which microcontroller does the Arduino Uno/Nano use?

Answer 4

ATmega328P.

Question 5

What is the clock speed of the ATmega328P?

Answer 5

16 MHz.

Question 6

How much Flash does the ATmega328P have?

Answer 6

32 KB.

Question 7

How much SRAM does the ATmega328P have?

Answer 7

2 KB.

Question 8

How much EEPROM does the ATmega328P have?

Answer 8

1 KB.

Question 9

What is Flash memory used for?

Answer 9

Storing program code (non-volatile).

Question 10

What is SRAM used for?

Answer 10

Variables, stack, temporary data (volatile).

Question 11

What is EEPROM used for?

Answer 11

Persistent storage of small data values.

Question 12

What is the Fetch–Decode–Execute cycle?

Answer 12

The CPU process: fetch instruction, decode it, then execute it.

Question 13

What is Harvard architecture?

Answer 13

Separate program and data memory for simultaneous access.

Question 14

What is Von Neumann architecture?

Answer 14

Program and data share the same memory and bus.

Question 15

Which architecture does the ATmega328P use?

Answer 15

Harvard architecture.

Question 16

How many general-purpose registers does the ATmega328P have?

Answer 16

32 (R0–R31).

Question 17

What is the SREG register?

Answer 17

Status Register containing CPU flags such as Zero, Carry, Negative, Overflow.

Question 18

What does the Zero (Z) flag represent?

Answer 18

An operation resulted in zero.

Question 19

What does the Carry (C) flag represent?

Answer 19

A carry or borrow occurred in arithmetic.

Question 20

What is the stack used for?

Answer 20

Function calls, return addresses, local variables, interrupt handling.

Question 21

Which register controls the stack?

Answer 21

Stack Pointer (SP).

Question 22

What does DDRx control?

Answer 22

Data Direction Register – sets pin as input (0) or output (1).

Question 23

What does PORTx do?

Answer 23

Sets output value or enables input pull-up resistors.

Question 24

What does PINx do?

Answer 24

Reads the logic level present on the input pins.

Question 25

Name the main I/O ports on the ATmega328P.

Answer 25

Port B, Port C, Port D.

Question 26

What is the purpose of the ADC?

Answer 26

Converts analog voltages into digital values (10-bit).

Question 27

What are timers used for?

Answer 27

Delays, counting events, PWM generation.

Question 28

What communication interfaces does the ATmega328P support?

Answer 28

USART, SPI, I2C (TWI).

Question 29

How can microcontroller power consumption be reduced?

Answer 29

Sleep modes, lowering the clock speed, disabling unused peripherals.

Question 30

Why is reliability important in embedded systems?

Answer 30

They often run continuously and unattended, so failures can be critical.