The IIT Madras BS Embedded C Programming (Embedded C Programming) End Term paper sat on 1 Sept 2024, in the May 2024 term, set QEF3: 23 questions for 50 marks in 180 minutes. Every question is below with its answer. Take it as a timed mock test to be marked, or read it through first.
Which of the following is a reason for designing a microcontroller (MCU) instead of using a microprocessor (MPU)?
To achieve higher computational power.
To minimize power consumption and extend battery life.
To accommodate larger on-chip memory capacity.
To simplify the design for general-purpose computing tasks.
Correct answer
To minimize power consumption and extend battery life.
Which instruction set architecture (ISA) is primarily associated with the Arduino platform?
AVR
ARM
MSP430
PIC
Correct answer
AVR
Which of the following data types would be most memory-efficient for storing the small integer number in an array, given that the maximum value of numbers can be 700?
int
unsigned int
uint8_t
uint16_t
Correct answer
uint16_t
A 12-bit ADC is used to digitize a signal in the range of -10V to +10V. What is the minimum difference (approx) between two voltages that you can measure?
2.5 mV
4.88 mV
6.88 mV
9 mV
Correct answer
4.88 mV
What is the primary advantage of Zigbee over WiFi for certain embedded system applications?
Higher data transfer rates
Longer range
Better security features
Lower power consumption
Correct answer
Lower power consumption
What is a circuit-switched connection?
A connection that breaks data into packets and sends them independently.
A dedicated path created between two endpoints.
A wireless connection established through Wi-Fi.
A protocol used for error detection in data transmission.
Correct answer
A dedicated path created between two endpoints.
How does loop unrolling optimize code execution in embedded systems?
By increasing the number of iterations.
By reducing the number of iterations and the overhead of loop control.
By combining multiple loops into one.
By eliminating the loop entirely.
Correct answer
By reducing the number of iterations and the overhead of loop control.
What is a common method microcontrollers use to manage power consumption?
Constantly running at maximum clock speed
Increasing voltage supply to all components
Utilizing multiple power modes such as sleep, standby, and shutdown
Disabling thermal management systems
Correct answer
Utilizing multiple power modes such as sleep, standby, and shutdown
BX = -4, CX = 16
BX = 4, CX = 16
BX = -4, CX = 20
BX = -4, CX = 12
Correct answer
BX = -4, CX = 16
What is a key benefit of using a microkernel architecture in embedded systems?
Enhanced graphical user interfaces
Increased direct hardware access
Strong isolation and modularity
Simplified debugging processes
Correct answer
Strong isolation and modularity
What type of error occurs due to asynchronous events and the order in which they occur?
Compilation error
Hardware error
Syntax error
Race condition
Correct answer
Race condition
What problem occurs when low-priority tasks never get CPU time due to continuous high-priority task execution?
Deadlock
Starvation
Priority Inversion
Concurrency
Correct answer
Starvation
You are developing firmware for a sensor node in a wireless sensor network. The node spends most of its time idle, waking up periodically to transmit data. What is the best optimization strategy to reduce power consumption?
Increase the processor clock speed to reduce the time spent in active mode.
Optimize the sensor data processing algorithm for faster execution.
Implement a deep sleep mode that turns off unnecessary peripherals when the node is idle.
Use a high-efficiency sorting algorithm for organizing transmitted data.
Correct answer
Implement a deep sleep mode that turns off unnecessary peripherals when the node is idle.
Which strategy is most effective for reducing leakage currents in an embedded system?
Using a lower clock frequency
Reducing the operating voltage
Implementing sleep modes for unused components
Increasing the transistor size
Correct answer
Implementing sleep modes for unused components
You are debugging an embedded system for a wearable fitness tracker that periodically measures and records heart rate data. You need to ensure that the system's timing is not affected by your debugging efforts. Which approach would you use to minimally impact the system's performance?
Correct answer
You are developing a video processing application that converts videos to different formats. After releasing the first version, you notice that the application takes a long time to process large video files. You decide to use a profiling tool to understand the performance issues. Question:
After profiling your application, you discover that a significant amount of time is spent on reading and writing video files to disk. What is the most effective optimization you could implement to improve the application's performance?
Rewrite the file I/O operations using a different programming language.
Optimize the video compression algorithm to reduce processing time.
Implement a buffering system to minimize disk I/O and process data in memory.
Increase the application's logging level to track more detailed processing steps.
Correct answer
Implement a buffering system to minimize disk I/O and process data in memory.
The process of identifying potential ethical dilemmas, evaluating options, making decisions, and learning from the outcomes is known as:
Ethical framework
Guided decision making
Ethical dilemma
Ethical reasoning
Correct answer
Guided decision making
0x20
0x40
0x10
0x80
Correct answer
0x40
A CPU has 128KB of SRAM connected to it starting at address 0x00300000. What is the address of the last byte in the SRAM?
0x0031FFFF
0x00320000
0x00303FFF
0x0030FFFF
Correct answer
0x0031FFFF
A memory-mapped peripheral has a register set starting at address 0x12345600. Each register is 16 bits wide. If there are 8 registers in the set, what is the address of the 4th register?
0x12345606
0x1234560C
0x12345608
0x12345610
Correct answer
0x12345608
Let's use the example of a finite state machine (FSM) for controlling an LED with a single button. The states and events will be defined as follows:
Consider the following code.
void handleEvent(Event_t event) { switch (currentState) { case STATE_OFF: if (event == EVENT_BUTTON_PRESS) { currentState = STATE_ON; } break; case STATE_ON: if (event == EVENT_BUTTON_PRESS) { currentState = STATE_BLINKING; }
break; case STATE_BLINKING: if (event == EVENT_BUTTON_PRESS || event == EVENT_BLINK_DONE) { currentState = STATE_OFF; } break; default: currentState = STATE_OFF; break; } }Which of the following transitions would occur if the current state is STATE_BLINKING and the EVENT_BLINK_DONE event occurs?
Transition to STATE_ON
Transition to STATE_OFF
Transition to STATE_ERROR
Transition to STATE_IDLE
Correct answer
Transition to STATE_OFF
Given the following FreeRTOS code for an Arduino project:
#include <Arduino_FreeRTOS.h>
void Task1(void *pvParameters) { for (;;) { Serial.println("Task 1"); vTaskDelay(1000 / portTICK_PERIOD_MS); }}
void Task2(void *pvParameters) { for (;;) {
Serial.println("Task 2"); vTaskDelay(500 / portTICK_PERIOD_MS); }}
void setup() { Serial.begin(9600); xTaskCreate(Task1, "Task 1", 128, NULL, 1, NULL); xTaskCreate(Task2, "Task 2", 128, NULL, 1, NULL); vTaskStartScheduler();}
void loop() {}What does the function xTaskCreate() do in the FreeRTOS setup?
It starts the scheduler to manage task execution.
It ends the task and frees resources.
It delays the execution of a task.
It creates a new task and adds it to the ready list.
Correct answer
It creates a new task and adds it to the ready list.
A 8-bit ADC can digitize an analog value into ___ distinct levels.
Correct answer: 256