Embedded Systems Questions and Answers

Answer: A

The defining feature is dedication rather than size: a washing machine controller and an engine management unit are both embedded because each does one job inside a product. Many carry a full operating system, and some are physically large.

Answer: B

Correct answer: an embedded system

An embedded system is a computer dedicated to controlling the product it is part of, rather than running whatever the user chooses. That dedication is what shapes everything about it - fixed function, tight cost and power limits, real-time deadlines, and often no operating system at all. The great majority of processors manufactured go into such systems rather than into computers recognisable as computers.

Answer: C

Users do not add applications to a brake controller, and the software is fixed at manufacture or by a controlled update. Timing constraints, resource limits and long unattended operation are all typical, and the first two often conflict with each other.

Answer: D

Deadlines and the cost and power emphasis are both characteristic. Single-chip construction is common but far from universal: an avionics computer or a car's infotainment unit is an embedded system spread over many devices and several boards.

Answer: A

Sharing the path means an instruction fetch and a data access cannot happen in the same cycle, which is the von Neumann bottleneck. The Harvard organisation splits them and can do both at once, at the cost of more silicon and more pins.

Answer: B

The name comes from the Harvard Mark I, whose program was on punched tape and data in relay counters. Most small microcontrollers use it because the fetch and the data access proceed in parallel, which raises throughput at a given clock rate.

Answer: C

Constant tables, string literals and calibration data have to live somewhere, and putting them in program memory is cheap. Allowing the program bus to be read as data keeps the parallel fetch while making that possible, which is why almost every real device is of this kind.

Answer: D

Correct answer: both statements are true and the second explains the first

Both are true and the second is the reason for the first. Separate program and data buses mean an instruction fetch and a data access use different physical paths, so they can proceed in the same cycle instead of competing. A von Neumann machine shares one bus and must serialise them - the bottleneck the Harvard architecture exists to remove, which is why it dominates in microcontrollers and digital signal processors.

Answer: A

Regularity is the point: a fixed format is easy to decode and easy to pipeline, and the compiler is left to build complex operations from simple ones. Only load and store touch memory, which keeps the pipeline predictable.

Answer: B

Confining memory traffic to explicit load and store instructions is what makes the timing of every other instruction predictable, which matters as much for real time work as for pipelining. A CISC machine allows an add to fetch an operand from memory.