Difficulty: Easy & Basic
What is the primary purpose of an embedded system?
A General desktop work
B A dedicated function
C Unlimited cloud storage
D Manual circuit drawing
Answer: B. A dedicated function. It combines computing hardware and software for a specific application.
Which component integrates a CPU, memory and peripherals on one chip?
A Microcontroller
B Relay
C Sensor
D Display
Answer: A. Microcontroller. A microcontroller commonly includes a processor, memory and peripheral interfaces.
Where is executable firmware usually retained when power is removed?
A Flash memory
B SRAM
C CPU register
D Cache
Answer: A. Flash memory. Nonvolatile flash retains program code without power.
During execution, where are temporary variables commonly stored?
A Flash
B ROM
C RAM
D EEPROM
Answer: C. RAM. RAM provides writable working storage during execution.
What converts a physical quantity into an electrical input signal?
A Sensor
B Actuator
C Oscillator
D Regulator
Answer: A. Sensor. Sensors detect quantities such as temperature or pressure.
Which device turns a controller command into physical action?
A ADC
B Sensor
C Actuator
D Memory
Answer: C. Actuator. An actuator can move or operate a mechanical load.
A temperature sensor outputs a voltage. Which peripheral digitizes it?
A DAC
B ADC
C UART
D GPIO
Answer: B. ADC. An analog-to-digital converter turns the voltage into a digital value.
Which peripheral reads or drives a digital pin?
A ADC
B EEPROM
C PLL
D GPIO
Answer: D. GPIO. General-purpose input/output pins handle digital logic levels.
How can a controller vary average power with digital pulses?
A PWM
B ROM
C UART
D CRC
Answer: A. PWM. Pulse-width modulation changes the fraction of each cycle spent high.
For periodic events, which peripheral counts clock ticks?
A Comparator
B ADC
C Timer
D Transceiver
Answer: C. Timer. A timer or counter advances with its configured clock source.
What alerts a processor to an event without continuous polling?
A Cache
B Interrupt
C Flash erase
D Linker
Answer: B. Interrupt. An interrupt invokes a handler when an enabled event occurs.
Software has stalled. Which peripheral can reset the controller after a timeout?
A ADC
B SPI controller
C GPIO
D Watchdog timer
Answer: D. Watchdog timer. The watchdog triggers recovery if software fails to service it in time.
Which serial interface commonly sends data without a shared clock line?
A UART
B SPI
C I2C
D JTAG
Answer: A. UART. UART uses agreed timing and framing for asynchronous serial data.
What does SPI normally use to synchronize bit transfers?
A Reset line
B Clock signal
C Analog reference
D Watchdog pulse
Answer: B. Clock signal. The SPI controller supplies a serial clock for transfer timing.
Which pair names the two I2C bus signals?
A MOSI and MISO
B TX and RX
C SWDIO and SWCLK
D SDA and SCL
Answer: D. SDA and SCL. I2C uses serial data SDA and serial clock SCL.
What is firmware in a typical controller?
A A power connector
B A heat sink
C A circuit enclosure
D Device control software
Answer: D. Device control software. Firmware is software stored for controlling the device.
Before the application runs, what can a bootloader do?
A Measure shaft torque
B Amplify sensor voltage
C Load or update firmware
D Provide mains power
Answer: C. Load or update firmware. A bootloader can initialize the device and start or update an application image.
Which RTOS facility chooses the next ready task?
A ADC
B Scheduler
C Bootloader
D Oscillator
Answer: B. Scheduler. The scheduler allocates CPU execution to ready tasks.
In a real-time task, what must be met for correct timing?
A Deadline
B Screen resolution
C File extension
D Pin count
Answer: A. Deadline. Real-time correctness includes meeting specified timing constraints.
Code is built on a desktop for another processor. Which tool does this?
A Cross compiler
B Logic analyzer
C Voltage regulator
D Oscilloscope
Answer: A. Cross compiler. A cross compiler generates code for a target architecture different from its host.
For debugging many Cortex-M devices, which interface is used?
A HDMI
B SATA
C VGA
D SWD
Answer: D. SWD. Serial Wire Debug supports programming and processor debugging.
Configuration must survive power loss and allow rewriting. Which memory fits?
A SRAM
B Register file
C EEPROM
D Cache
Answer: C. EEPROM. EEPROM is nonvolatile and electrically rewritable.
If clock frequency is 1 MHz, one cycle lasts how long?
A 1 nanosecond
B 1 microsecond
C 1 millisecond
D 1 second
Answer: B. 1 microsecond. The period is the reciprocal of 1,000,000 cycles per second.
What action restarts the controller from its initial state?
A Sleep
B Interrupt masking
C Polling
D Reset
Answer: D. Reset. A reset reinitializes processor operation and startup state.
Which operating mode often reduces idle power consumption?
A Busy loop
B Maximum clock
C Sleep mode
D Continuous transmission
Answer: C. Sleep mode. Sleep modes suspend selected activity to save power.