CPU/Microprocessor

Question 1

Each instruction executed by the CPU requires what?

Answer 1

Memory access

Question 2

Primary memory holds?

Answer 2

Program instructions and data

Question 3

Secondary storage holds?

Answer 3

Long term storage

Question 4

Data is moved from where to where for CPU execution?

Answer 4

Secondary storage to primary memory

Question 5

What is the Little Man Computer (LMC)?

Answer 5

An instructional model of a computer that models a simple von neumann architecture computer, which has all the basic features of a modern computer.

Question 6

What is von neumann architecture?

Answer 6

Memory holds both programs and data, memory is addressed linearly, memory is addressed by the location number without regard to the data contained within.

Question 7

How many LMC mailboxes?

Answer 7

There are 100, addressed 0-99.

Question 8

Contents of LMC mailboxes:

Answer 8

Each mailbox is designed to hold a single slip of paper, with a three digit decimal number. The contents are not the same as the address

Question 9

LMC calculator:

Answer 9

Simple, used to enter and temporarily hold numbers, add and subtract.

Question 10

Hand counter/instruction location counter:

Answer 10

There is a two digit hand counter, you click to increment the count and there is a reset button.

Question 11

Little man:

Answer 11

Performs certain tasks, interacting with the outside world through an in basket and out basket

Question 12

Some LMC instructions:

Answer 12

LOAD: LM walks to mailbox address from the instruction, reads the three digit number and punches it into the calculator
STORE: LM walks to calculator, reads the number, stores it in mailbox address whos address is in the instruction
ADD: LM walks to mailbox address, reads number, adds to the number already in the calculator. The number in the mailbox is unchanged.
SUBTRACT: same but with subtraction
INPUT: LM walks to in basket and picks up the paper, and enters it into the calculator. The number isn’t in the basket anymore and whatever was in the calculator has been replaced.
OUTPUT: LM walks to calculator, writes number, goes to the out basket and places the paper
HALT: stop!

Question 13

CPU/LM instruction cycle:

Answer 13

The instruction cycle is the steps that the LM takes to perform an instruction

Question 14

The instruction cycle can be split into what two parts?

Answer 14

The fetch portion, in which LM finds out what instruction he is to execute, and
The execute portion, in which LM actually performs the work specified in the instruction

Question 15

What are the components of the computer unit?

Answer 15

ALU, Control Unit (CU), and memory