Computer Architecture Midterm

Question 1

Performance

Answer 1

Parallelisms, pipelining, prediction.

Question 2

System software

Answer 2

Operating system and compiler

Question 3

Handled by operating system

Answer 3

IO, memory, CPU queue

Question 4

Datapath

Answer 4

Performs operations on data

Question 5

Control

Answer 5

Combines Datapath and memory together

Question 6

Integrated circuit manufacturing

Answer 6

Ingot -> wafer -> patterned wafer -> die

Question 7

Semiconductor

Answer 7

Can act as conductor or insulator

Question 8

N-Type doping

Answer 8

Uses phosphorus or arsenic to create a free to wander electron

Question 9

P-Type doping

Answer 9

Uses Gallium or Born so there is one too few electrons.

Question 10

Junction diode

Answer 10

Allows current to flow in one direction, but not in the other. The free electrons from N-Type doping fill the holes from P-Type doping.

Question 11

Depletion zone

Answer 11

Electrically neutral area created after flow through a junction diode is complete.

Current flows again only if N-Type area is connected to negative and P-Type to possitive.

Question 12

Transistor design

Answer 12

Loops like PNP with a gate between the middle to allow or disallow flow.

Question 13

Not gate

Answer 13

Uses one transistor

Question 14

Nand gate

Answer 14

Uses two transistors in parallel.

Question 15

And gate

Answer 15

Some transistors

Question 16

Nand gate

Answer 16

Some transistors

Question 17

Or gate

Answer 17

Some transistors

Question 18

Combinational circuit

Answer 18

No memory - output is determined only by inputs

Question 19

ALU

Answer 19

Can be used for adding and for checking equality

Question 20

Verilog special values

Answer 20

x - value is unknown. This includes being fed two conflicting values.
z - wire is disconnected.

Question 21

Sequential circuits

Answer 21

Depends on input and state

Question 22

Memory

Answer 22

Needs to let you read the value, write the value to true or false, and otherwise store the value.

Question 23

Saturation time and propagation delay

Answer 23

Physical limit of how can you can read and write memory

Question 24

A Four Bit Register

Answer 24

Has two inputs and four outputs. Inputs are to read or write and whether its locked or not. There are four output wires that will contain data being read. Uses four D-Latch locks.

Question 25

Decoder

Answer 25

Used to address into memory. If you take in four bits of input, you can access one of 2^4 pieces of memory.

Question 26

Static RAM

Answer 26

Caches built from sequential circuits, not combinational. Uses 4-6 transistors. < 1ns access possible

Question 27

Dynamic RAM

Answer 27

Single transistor and a capacitor. Much more dense layout.

Question 28

Latch

Answer 28

Type of bi-stable storage ellement.

Question 29

Simplest latch for bi-stable memory

Answer 29

Two not gates

Question 30

SR Latch

Answer 30

Uses two nor gates connected to each other. S&R are input and Q and Q' are outputs. 00 - store 10 - set 01 - reset 11 - infinite loop