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How many bits would be required for the op code portion of the instructions in a 16 bit binary machine?

10 instructions require 4 bits

How many mailboxes could a 16bit binary machine accommodate?

16 - 4 (bits for instructions (10)) = 12 for addresses. 2^12 mailboxes

quality attributes of IT infrastructure

Availability, Performance, Security

Dynamic (DRAM)

Cheap, Less heat/power

Infrastructure Building blocks

End User Devices, Operating Systems, Compute, Storage, Networking, Data-centers

Static (SRAM)

Faster, Does not need to be refreshed, Used in cache memory for high speed

The instruction cycle is divided into two phases: what is the purpose of the first phase?

Fetch and Execute Fetch is designed to help the "little man" find what he needs to execute

What does the Little Man do during the second phase of a COFFEE BREAK or HALT instruction?

It stops executing.

What are the criteria that define a von Neumann architecture?

Stored program concept & Memory holds data and programs and is addressed by location number

What are the four primary operations that are normally performed on a register?

Stores values from other locations Addition and subtraction Shifts or rotates data Test contents for conditions such as zero or positive

What is a bus? What are buses used for?

The physical connection that makes it possible to transfer data from one location in the computer system to another

Why are there two different registers (MAR and MDR) associated with memory?

With only one memory register, storing data would overwrite its address, losing its location

What is a register?

a high speed storage area within a computer

Program Counter (PC) Register

contains the address of the current instruction or the next instruction to be executed

Memory Data Register (MDR)

holds a data value that is being stored to or retrieved from the memory location currently

Memory Address Register (MAR)

holds the address of a memory location

Instruction Register (IR)

holds the instruction being executed currently by the computer

Non-Volatile

is permanent in nature. remains even after the system is turned off

point-to-point bus

point-to-point connection the link is only between two devices

bus categories

serial and parallel

volatile memory

temporary in nature.Stores the data inside it only while power is supplied.

multi-point bus

the link is between a sender and multiple receivers.