How do you include an external library in your Arduino sketch?

a$.$ import

b$.$ load

c$.$ #include

d$.$ require

e$.$ None of the above $22.$ Which keyword is used to define an array in Arduino?

a$.$ list

b$.$ vector

c$.$ array

d$.$ None of the above

$23.$ Which library is used for I$2$C communication?

a$.$ SPI

b$.$ Wire

c$.$ Serial

d$.$ Ethernet

e$.$ None of the above

$24.$ How do you include an external library in your Arduino sketch?

a$.$ import

b$.$ load

c$.\backslash$#include

d$.$ require

e$.$ None of the above

$25.$ What does the following code output?

c

Copy code

int arr$[]=\backslash \{10,20,30\backslash \}$;

Serial.print$($arr$[1])$;

a$.10$

b$.20$

c$.30$

d$.0$

e$.$ None of the above

Section $6$: Interrupts and Timers

$26.$ What is the purpose of a hardware interrupt in Arduino?

a$.$ To generate random numbers

b$.$ To pause the microcontroller indefinitely

c$.$ To respond immediately to external events

d$.$ To control PWM signals

e$.$ None of the above

$27.$ Which function is used to attach an interrupt to a pin in Arduino?

a$.$ interruptAttach$()$

b$.$ pinInterrupt$)$

c$.$ attachInterrupt$()$

d$.$ setInterrupt$()$

e$.$ None of the above

$28.$ What is the name of the timer configuration register for Timer $1$ on the ATmega$328?$

a$.$ TCCR$1$A

b$.$ TCCR$0$B

c$.$ TMR$1$

d$.$ TIMER$1\_$CFG

e$.$ None of the above

$29.$ Which timer mode allows for precise interval measurement in Arduino?

a$.$ Normal mode

b$.$ PWM mode

c$.$ CTC mode

d$.$ Fast PWM mode

e$.$ None of the above $30.$ What is the maximum value of Timer $0$ on an Arduino Uno?

a$.1023$

b$.255$

c$.511$

d$.4095$

e$.$ None of the above

Section $7$: Watchdog Timers

$31.$ What is the primary purpose of the watchdog timer?

a$.$ To prevent overheating of the Arduino board

b$.$ To reset the microcontroller if it becomes unresponsive

c$.$ To manage power consumption

d$.$ To control peripheral devices

e$.$ None of the above

$32.$ Which register is used to configure the watchdog timer on an ATmega$328?$

a$.$ WDTCSR

b$.$ WD$\_$CFG

c$.$ WDTSET

d$.$ TCCR$\_$WDT

e$.$ None of the above

$33.$ What happens when the watchdog timer is not reset in time?

a$.$ The program restarts from the beginning

b$.$ The microcontroller enters sleep mode

c$.$ The program continues as normal

d$.$ A warning message is sent to the Serial Monitor

e$.$ None of the above

$34.$ Which function is used to reset the watchdog timer in Arduino?

a$.$ watchdogReset $()$

b$.$ wdt$\_$reset $()$

c$.$ resetWDT $()$

d$.$ clearWatchdog$()$

e$.$ None of the above

$35.$ What is the typical timeout period of the watchdog timer in Arduino?

a$.15$ ms

b$.500$ ms

c$.1$ second

d$.$ Configurable

e$.$ None of the above

Section $8$: Sleep Modes and Power Management

$36.$ Which library is commonly used for sleep modes in Arduino?

a$.$ Timer

b$.$ Wire

c$.$ LowPower

d$.$ Serial

e$.$ None of the above

$37.$ Which sleep mode consumes the least power on the ATmega$328?$

a$.$ Idle mode

b$.$ Power$-$save mode

c$.$ Power$-$down mode

d$.$ ADC noise reduction mode

e$.$ None of the above

$38.$ What is the primary purpose of sleep modes in microcontrollers?

a$.$ Increase clock speed

b$.$ Reduce power consumption

c$.$ Improve sensor accuracy

d$.$ Maintain serial communication

e$.$ None of the above

$39.$ What can wake up the Arduino from sleep mode?

a$.$ External interrupt

b$.$ Watchdog timer

c$.$ Serial data reception

d$.$ All of the above

e$.$ None of the above

$40.$ Which function is used to enable sleep mode?

a$.$ entersleep $()$

b$.$ sleepMode $()$

Extra Credit: Wireless Communication

$46.$ Which of the following modules supports Bluetooth communication with Arduino?

a$.$ ESP$8266$

b$.$ HC$-05$

c$.$ nRF$24$L$01$

d$.$ Zigbee

e$.$ None of the above

$47.$ What is the frequency band of the nRF$24$L$01$ module?

a$.433$ MHz

b$.2\mathrm{.}4$ GHz

c$.5$ GHz

d$.900$ MHz

e$.$ None of the above

$48.$ Which library is used to communicate with Wi$-$Fi modules like the ESP$8266?$

a$.$ SPI

b$.$ Wire

c$.$ WiFi

d$.$ Ethernet

e$.$ None of the above $49.$ What is the primary function of the MQTT protocol in wireless communication?

a$.$ File sharing

b$.$ Messaging between IoT devices

c$.$ Wireless firmware updates

d$.$ Remote debugging

e$.$ None of the above

$50.$ Which Arduino board comes with built$-$in Wi$-$Fi and Bluetooth capabilities?

a$.$ Arduino Uno

b$.$ Arduino Nano

c$.$ Arduino Nano $33$ IoT

d$.$ Arduino Mega

e$.$ None of the above