1What core microcontroller serves as the brain for the Arduino Uno R3?
ATmega328P
2What is the name for the programs written and compiled in the Arduino IDE?
Sketches
3What is the primary purpose of the Wiring library in Arduino?
To simplify microcontroller control and conceal low-level hardware details for beginners.
4How many pins are required for a 4x4 matrix keypad to read 16 individual switches?
8 pins (4 rows and 4 columns)
5What technique does the Arduino use to determine which key on a matrix keypad is pressed?
Matrix scanning (sending signals across columns and reading row states)
6What happens electrically when a keypad button is pressed?
It creates a physical connection between a specific row and a specific column.
7Why is proper pin assignment crucial when connecting a keypad to the Arduino?
To ensure the software grid map matches the physical wiring so key presses are read accurately.
8What function in the provided code is used to check for an input from the keypad?
keypad.getKey()
9In the lab activity, which digital pins were assigned to the rows?
Pins 9, 8, 7, and 6
10In the lab activity, which digital pins were assigned to the columns?
Pins 5, 4, 3, and 2
11What protocol does the 16x2 LCD use to communicate with the Arduino using pins A4 and A5?
I2C communication
12What is the common I2C device address for the simulated LCD in Tinkercad?
0x20
13What is a common I2C device address for physical LCD hardware modules?
0x27
14What is the purpose of the "if (key)" condition in the code loop?
To verify a legitimate key event occurred before updating the screen, preventing flicker.
15What term describes the reduction of mechanical noise generated when a button is pressed?
Debouncing
16What happens to the LCD display when no key is detected by the program?
The LCD refresh is skipped, keeping the current display content and avoiding idle corruption.
17Which library must be included to handle the characters and intersections of the keypad?
Keypad.h
18What specific character array structure is used to define the layout of the keypad in the code?
A 2D array (char keys[4][4])
19Where does the Arduino code typically print the character on the LCD screen?
The top-left corner (after using lcd.clear())
20What hardware component provides the clock signal for the microcontroller on the board?
Crystal oscillator
21A device that uses high-pitch sound waves beyond human hearing to determine distance
Ultrasonic Distance Sensor
22A piece of electronic test equipment used to observe signal characteristics like amplitude and phase shifting
Oscilloscope
23The process where a digital oscilloscope converts analog signals for storage and display at a variable rate
Sampling
24The physical principle representing the duration from when a wave is emitted until it returns
Round-trip echo time (Time of Flight)
25The visual behavior of the oscilloscope pulse as an object moves closer to the sensor
It becomes narrower
26The visual behavior of the oscilloscope pulse as an object moves further from the sensor
It becomes wider
27The absolute maximum continuous current limit for an Arduino Uno R3 digital pin
40.0 mA
28The specific current drawn by the DC motor in the simulation that triggered an overcurrent alert
44.4 mA
29A switching component used to safely isolate high-current actuators from a microcontroller
NPN Transistor (e.g., 2N2222)
30The distance threshold at which the control logic activates the LED and Motor
10.0 inches
31The maximum detection distance recorded for the ultrasonic sensor in this activity
132.4 inches
32The specific mathematical factor used in the code to convert duration to inches
147.5
33A hardware adjustment to reduce acoustic energy loss in the air for longer range
Lower the frequency (e.g., 20-25 kHz)
34The alternative technology recommended if atmospheric sound attenuation limits detection
LiDAR or Radar
35A software method used to ignore random echo spikes and false triggers in noisy environments
Moving average or median filter
36A hardware modification, such as a foam shield or cone, to block ambient side noise
Acoustic baffling
37The programming requirement for a 3-pin ultrasonic sensor signal pin
Switching between OUTPUT and INPUT modes
38The benefit of pulling motor current from a power rail via a transistor rather than a digital pin
Prevents inductive electrical noise and voltage dips