1.1.1 Table

Question 1

CPU

Does what with what?
In terms of what does the user think of these?

Answer 1

Machine instructions perform operations on contents of registers and memory locations.

The user thinks in terms of arrays, lists, and other high-level data structures, accessed and manipulated by corresponding high-level operations.

Question 2

Main memory
[also known as primary memory or RAM (Random Access Memory), is a type of computer memory that is directly accessible by the CPU (Central Processing Unit). It is used to store data and instructions that are actively being processed by the CPU.]

What is physical memory?

What type of entities does the user manage?

Answer 2

Physical memory is a linear sequence of addressable bytes or words that hold programs and data.

The user must manage a heterogeneous collection of entities of various types and sizes, including source and executable programs, library functions, and dynamically allocated data structures, each accessed by different operations.

Question 3

Secondary storage

Where?
Requires what?

The user does what?

Answer 3

Disk and other secondary storage devices are multi-dimensional structures, which require complex sequences of low-level operations to store and access data organized in discrete blocks.

The user needs to access and manipulate programs and data sets of various sizes as individual named entities without any knowledge of the disk organization.

Question 4

I/O devices

How do they operate?

What does the user need?

Answer 4

I/O devices are operated by reading and writing registers of the device controllers.

The user needs simple, uniform interfaces to access different devices without detailed knowledge of the access and communication protocols.