Unisys Internship Trainee Interview Questions and Answers

Interrupts in microprocessors are signals that temporarily halt the normal execution of a program to handle a specific event or request.

• Interrupts are used to handle time-critical events or to interface with external devices.

• They allow the microprocessor to respond to external stimuli without constantly checking for them.

• Interrupts have different priority levels and can be masked or enabled/disabled.

• Examples of interru...read more

Timers in microprocessors are hardware components that measure and control time intervals. They can be triggered by external events or programmed instructions.

• Timers in microprocessors are used for various purposes such as generating accurate time delays, measuring time intervals, and controlling the execution of tasks.

• They are typically implemented as hardware registers that count clock cycles or external events.

• Timer...read more

The fundamental principle of an operational amplifier (OPAMP) is to amplify the difference between the input voltages.

• OPAMP amplifies the voltage difference between its two input terminals

• The output voltage of an OPAMP is proportional to the difference between the input voltages

• OPAMP has a high gain and high input impedance

• The input terminals of an OPAMP draw negligible current

• OPAMP operates in a closed-loop configurat

Optical fiber is a technology that uses thin strands of glass or plastic to transmit data as pulses of light.

• Optical fibers are made of a core, cladding, and a protective outer layer.

• Light signals are transmitted through the core of the fiber by bouncing off the cladding due to total internal reflection.

• Fiber optic cables can transmit data over long distances with minimal loss of signal strength.

• They are used in teleco...read more

Losses in optical fibre include attenuation, dispersion, and bending losses.

• Attenuation is the reduction in signal strength as it travels through the fibre.

• Dispersion is the spreading of the signal due to different wavelengths traveling at different speeds.

• Bending losses occur when the fibre is bent too tightly, causing signal loss.

• Other losses include splice losses, connector losses, and modal noise.

PWM stands for Pulse Width Modulation. It is a technique used to control the amount of power delivered to a device by varying the width of the pulse of a periodic signal.

• PWM is commonly used in electronic devices to control the speed of motors or the brightness of LEDs.

• It works by rapidly switching a signal between ON and OFF states at a fixed frequency.

• The ratio of the ON time to the total period is called the duty cy...read more

Optical fibre communication takes place at different wavelengths, with some providing better performance than others.

• Optical fibre communication can take place at various wavelengths, including 850 nm, 1310 nm, and 1550 nm.

• The 850 nm wavelength is commonly used for short-distance communication, such as within buildings or data centers.

• The 1310 nm wavelength is often used for medium-distance communication, such as metro...read more

Servo motors are devices that convert electrical signals into precise mechanical motion.

• Servo motors are commonly used in robotics and automation systems.

• They consist of a motor, a control circuit, and a feedback mechanism.

• Servo motors are capable of rotating to a specific angle and maintaining that position.

• They are often used in applications that require accurate positioning, such as robotic arms or camera gimbals.

• Se...read more