Embedded Systems Quiz - Advanced to Expert

You need to reduce electromagnetic interference (EMI) in a high-speed embedded system. Which solution is most effective?

• Use long wires

• Enable pull-up resistors

• Add ground planes and proper trace impedance matching

• Reduce voltage only

In an RTOS system, tasks are missing deadlines under high load. What is a robust corrective measure?

• Increase task priority randomly

• Use fixed priority without deadlines

• Perform rate-monotonic or EDF scheduling analysis

• Disable interrupts

A system must process sensor data, apply a Kalman filter, and control a motor in real-time. What architecture is ideal?

• Single-threaded with polling

• Interrupt-based state machine

• RTOS with dedicated threads for sensor, filter, and actuator

• Bare-metal infinite loop

During testing, your embedded Linux system locks up when writing to NAND flash. Cause?

• Flash is full

• Wear leveling failure or improper MTD driver usage

• Incorrect GPIO

• Floating point exception

A real-time system is sensitive to jitter. Which strategy minimizes it?

• Use cooperative scheduling

• Allocate dynamic memory inside ISR

• Use preemptive RTOS with priority inheritance and pin ISR

• Use high baud rate UART

You’re using SPI on two slave devices. One receives corrupt data. Root cause?

• Clock skew and lack of tri-state MISO management

• Interrupt priority mismatch

• Shorted pull-up

• I2C instead

Your embedded vision system needs fast AI inference. Which is ideal?

• Use CPU with delay

• Use MCU with floating point

• Integrate NPU/TPU accelerator (e.g., Coral, EdgeTPU)

• Use EEPROM

A motor controller using a PID algorithm oscillates heavily. What’s the remedy?

• Reduce sampling rate

• Fine-tune gains and add derivative filtering

• Switch to PWM

• Remove proportional gain

Your CAN-based embedded system exhibits bus-off errors. What should you do?

• Reduce supply voltage

• Increase baud rate

• Monitor bus load, check termination and software retries

• Switch to UART

A real-time embedded system with FreeRTOS runs out of heap. What’s a good strategy?

• Switch to polling

• Increase configTOTAL_HEAP_SIZE and use heap_4.c

• Reduce baud rate

• Print heap values