ARDUINO WORKSHOP

Which of the following statements about the VIN pin on the Arduino Uno is TRUE?

• It provides a constant 3.3V output.

• It is used to power the board when using an external power source.

• It can be used to read analog voltages.

• It is a ground pin used for circuit protection.

What is the default resolution of analogRead() on the Arduino Uno?

• 8-bit (0 - 255)

• 10-bit (0 - 1023)

• 12-bit (0 - 4095)

• 16-bit (0 - 65535)

Which pin(s) on the Arduino Uno are officially hardware PWM capable?

• D2, D4, D6, D8, D12

• D3, D5, D6, D9, D10, D11

• D1, D2, D3, D9, D10, D13

• All digital pins (D0 - D13)

The built-in LED on the Arduino Uno is connected to which pin?

• D1

• D5

• D10

• D13

If you use analogWrite(9, 127);, what voltage (approximately) will appear at pin D9?

• 1.25V

• 2.5V

• 3.75V

• 5V

Answer explanation

Since 127 is approximately 50% of 255, the output voltage is 50% of 5V, which is 2.5V.

What is the purpose of the attachInterrupt() function in Arduino?

• It enables a timer interrupt for delay calculations.

• It stops the execution of loop() and jumps to another function.

• It links an external event to an interrupt service routine (ISR).

• It allows the Arduino to communicate over I2C.

Which of the following digital pins on the Arduino Uno are also used for I2C communication?

• D2,D3

• D10,D11

• A4,A5

• D0,D1

Answer explanation

A4 = SDA, A5 = SCL for I2C communication

What is the function of the SPI SS (Slave Select) pin on the Arduino Uno?

• It controls the reset function of SPI-connected devices.

• It acts as a data transmission line for SPI communication.

• It enables or disables communication with a specific SPI device.

• It is only used for UART communication.

Which of these communication protocols is used by the Arduino Uno’s serial monitor?

• 12C

• SPI

• UART

• PWM

Answer explanation

UART (TX/RX on D0, D1) is used for serial communication with the Serial Monitor.

What happens if you set pinMode(A0, OUTPUT); on an Arduino Uno?

• A0 will function as a digital output pin.

• The Arduino will crash because A0 is strictly analog-only.

• A0 will send analog voltage values to Serial Monitor.

• A0 will read sensor values as usual

Answer explanation

Analog pins A0 - A5 can be used as digital I/O when set as OUTPUT.