1.1 structure of the CPU

Question 1

list of all regsiters

Answer 1

MAR
MDR
CIR
Program counter
accumulator

Question 2

what is a register

Answer 2

temporary small storage
used for a specific purpose
faster than RAM
used in FDE cycle

Question 3

what does the control unit do

Answer 3

the control unit decodes instructions
sends signals to control movement of data
uses control buses

Question 4

what are the three buses

Answer 4

address bus
control bus
data bus

Question 5

what does the address bus do

Answer 5

sends the address of the address in the main memory

Question 6

what does the control bus

Answer 6

transmits control signals
essentially tells the the CPU if data is being written to or read from memory

Question 7

what does the address bus do

Answer 7

used by the CPU to locate the physical address in the MAR

Question 8

what is a bus

Answer 8

busses consist of a series of connectors that transfer signals between internal components
signals typically 16 32 64 bits

Question 9

what is the CIR

Answer 9

current instriction register if data sent to the MDR is an instruction and not data then copied over to the current instruction register

Question 10

what is the general purpose register

Answer 10

contains any number overflows

Question 11

Characteristics of Von neumann

Answer 11

one control unit
one bus for both instructions and data
single processor (can have multiple cores)
one instruction at a time
program must be loaded into main memory to be executed
instructions and data stored together

Question 12

characteristics of Harvard arhchitecture

Answer 12

instructions and data in seperate memory locations
two seperate buses for data and instructions
can fetch instructions and data at the same time