Embedded C 面试题与答案

问题 1. What is embedded C?

Embedded C is a set of extensions to the C programming language specifically designed for embedded systems.

问题 2. Explain the difference between a microcontroller and a microprocessor.

A microcontroller integrates a processor with peripheral devices like timers, communication ports, and memory on a single chip. A microprocessor, on the other hand, only includes the CPU.

问题 3. What is a volatile variable in C?

The volatile keyword tells the compiler that a variable's value may change at any time, without any action being taken by the code.

Example:

volatile int sensorValue;

问题 4. Explain the significance of the 'const' keyword in embedded C.

'const' is used to define constants in C, and in embedded systems, it helps in better code optimization and memory management.

Example:

const int MAX_SIZE = 100;

问题 5. What is the purpose of a watchdog timer in embedded systems?

A watchdog timer is used to reset the microcontroller if the software hangs or encounters an error, ensuring system reliability.