Embedded Systems H7061Z根据这个教材帮我出一份例卷

Embedded Systems (H7061Z) 例卷

Part A: Multiple Choice Questions

Which of the following is NOT a type of microcontroller? A. AVR B. PIC C. ARM D. FPGA Answer: D
Which of the following is an example of a real-time operating system (RTOS)? A. Linux B. Windows C. VxWorks D. macOS Answer: C
Which of the following is NOT a common communication interface used in embedded systems? A. I2C B. SPI C. USB D. HDMI Answer: D
Which of the following is a common programming language used in embedded systems? A. Python B. Java C. C D. Ruby Answer: C
Which of the following is the correct order of steps in the software development process? A. Design, implementation, testing, maintenance B. Testing, implementation, design, maintenance C. Implementation, testing, design, maintenance D. Design, testing, implementation, maintenance Answer: A

Part B: Short Answer Questions

What is an interrupt in an embedded system? Give an example of an interrupt. Answer: An interrupt is a signal that stops the normal flow of program execution and transfers control to a specific function called an interrupt service routine (ISR). An example of an interrupt is a timer interrupt, which occurs when a timer reaches a specified value and triggers an ISR to perform a specific task.
What is the difference between a microcontroller and a microprocessor? Answer: A microcontroller is a complete computer system on a single chip, including a processor, memory, and I/O interfaces. It is designed for embedded applications and typically has lower processing power than a microprocessor. A microprocessor, on the other hand, is a general-purpose CPU that requires external memory and I/O interfaces to function.
What is a watchdog timer? How is it used in embedded systems? Answer: A watchdog timer is a hardware timer that is used to detect and recover from system failures. It works by periodically resetting a counter and checking if the counter reaches a specified value within a certain time interval. If the counter does not reset within the specified time, the watchdog timer triggers a system reset to recover from the failure. Watchdog timers are commonly used in embedded systems to ensure system reliability and prevent system crashes.

Part C: Programming Exercise

Write a C program to interface a temperature sensor with an AVR microcontroller. The program should read the temperature data from the sensor using an I2C interface and display the temperature on an LCD display. Assume that the temperature sensor has an I2C address of 0x50 and the LCD display is connected to PORTD of the microcontroller.

#include <avr/io.h> #include <util/delay.h> #include <avr/interrupt.h> #include "i2c.h" #include "lcd.h"

#define TEMP_SENSOR_ADDR 0x50

int main(void) { uint8_t data[2]; int16_t temp;

i2c_init(); lcd_init();

while(1) { i2c_start(); i2c_write(TEMP_SENSOR_ADDR << 1); i2c_write(0x00); i2c_start(); i2c_write((TEMP_SENSOR_ADDR << 1) | 0x01); data[0] = i2c_read_ack(); data[1] = i2c_read_nack(); i2c_stop();

  temp = (data[0] << 8) | data[1];
  temp = (temp * 0.02) - 273.15;

  lcd_gotoxy(0,0);
  lcd_printf("Temperature: %dC", temp);

  _delay_ms(1000);

} }

Note: The above program assumes that the temperature sensor is a 2-byte device that sends the temperature data in Celsius. The program also assumes that the LCD display is connected to PORTD of the microcontroller using a standard 4-bit interface. The i2c.h and lcd.h header files are assumed to contain the necessary functions for I2C communication and LCD interfacing