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Added an introdution.

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John Winans 2018-05-04 00:01:11 -05:00
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3 changed files with 142 additions and 2 deletions
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2
book/book.tex
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@ -58,7 +58,7 @@
%\part{Introduction}
%\include{intro/chapter}
\include{intro/chapter}
\include{numbers/chapter}
\include{toolchain/chapter}
\include{rv32/chapter}

26
book/glossary.tex
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@ -5,6 +5,14 @@
for scientific documents}
}
\newglossaryentry{binary}
{
name=binary,
description={Something that has two parts or states. In computing
these two states are represented by the numbers one and zero or
by the conditions true and false and can be stored in one bit}
}
\newglossaryentry{bit}
{
name=bit,
@ -84,6 +92,23 @@
caused by low--order truncation}
}
\newglossaryentry{MachineLanguage}
{
name={machine language},
description={The instructions that are executed by a CPU that are expressed
in the form of binary values}
}
\newglossaryentry{register}
{
name={register},
description={A unit of storage inside a CPU}
}
\newglossaryentry{program}
{
name={program},
description={A ordered list of one or more instructions}
}
@ -91,3 +116,4 @@
\newacronym{msb}{MSB}{Most Significant Bit}
\newacronym{lsb}{LSB}{Least Significant Bit}
\newacronym{isa}{ISA}{Instruction Set Architecture}
\newacronym{cpu}{CPU}{Central Processing Unit}

116
book/intro/chapter.tex
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@ -1,10 +1,124 @@
\chapter{Introduction}
\label{chapter:Introduction}
At its core, a digital computer has at least one \acrfull{cpu}. A
CPU executes a continuous stream of instructions called a \gls{program}.
These program instructions are expressed in what is called
\gls{MachineLanguage}. Each machine language instruction is a binary value.
In order to provide a method to simplify the management of machine language
programs a symbolic mapping is provided where a mneumonic can be used to
specify each machine instruction and any of its parameters\ldots\ rather
than mandate that programs be expressed as binary machine language
instructions. The set of mneumonics, parameters and rules for specifying
them is called an {\em Assembly Language}.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\section{The Digital Computer}
A digital computer is composed of storage systems (memory, disc drives,
USB drives, etc.), a CPU (with one or more cores), input peripherals like
a keyboard and mouse and output peripherals like a display or speakers.
\subsection{Storage Systems}
Computer storage systems are used to hold the data and instructions
for the CPU.
Types of computer storage can be classified into two categories.
Volatile and non--volatile.
\subsubsection{Volatile Storage}
Volatile storage is characterized by the fact that it will lose its
contents (forget) any time that it is powered off.
One type of volatile storage is provided inside the CPU itself in
small blocks called \glspl{register}. These registers are used to
hold individual data values that can be manipulated by the instructions
that are executed by the CPU.
Another type of volatile storage is main memory.
Main memory is connected to a computer's CPU and is used to hold
the data and instructions that can not fit into the CPU registers.
Typically, a CPU's registers can hold tens of data values while
the main memory can contain many billions of data values.
A CPU can process data in a register at a speed that can be an order
of magnitude faster than the rate that it can process (specifically,
transfer data and instructions to and from) the main memory.
Register storage costs an order of magnitude more to manufacture than
main memory. While it is desirable to have many registers the economics
dictate that the vast majority of volatile computer storage be provided
in its main memory. As a result, optimizing the copying of data between
the registers and main memory is a desirable trait of good programs.
\subsubsection{Non--Volatile Storage}
Non--volatile storage is characterized by the fact that it will {\em NOT}
lose its contents when it is powered off.
Common types of non--volatile storage are disc drives, flash cards and USB
drives. Prices can vary widely depending on size and transfer speeds.
It is typical for a computer system's non--volatile storage to operate
more slowly than its main memory.
\subsection{CPU}
The \acrshort{cpu} is a collection of registers and circuitry designed
to read data and instructions from the system storage. The instructions
are used to instruct the CPU how to perform various mathamatical and
logical operations on the data in its registers and write the results
of those operations back into the system storage.
\subsection{Peripherals}
A peripheral is a device that is not a CPU or main memory. They are
typically used to transfer information/data into and out of the
main memory.
This text is not particularly concerned with the peripherals of a computer
system other than in those sections where instructions are discussed
whose purpose is to address the needs of a peripheral device. Such
instructions are used to initiate, execute and/or synchronize data transfers.
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\section{Instruction Set Architecture}
Discuss the IMAFD, G and other ISA extensions mean.
The catalog of rules that describe all of the details of the instructions
that a given CPU can execute is called its \acrfull{isa}.
The RISC--V CPU ISA is defined as a set of modules. The purpose of
dividing the ISA into modules is to allow an implementor to select which
features to incorporate into a CPU design.
Any given RISC--V implementation must provide one of the {\em base}
modules and zero or more of the {\em extension} modules.
\subsection{RV Base Modules}
The base modules are RV32I (32--bit general purpose),
RV32E (32--bit embedded), RV64I (64--bit general purpose)
and RV128I (128--bit general purpose).
These base modules provide the minimal functional set of integer operations
needed to execute an application. The differing bit--widths address
the needs of different main--memory sizes.
This text discusses programming the RV32I using assembly language.
\subsection{Extension Modules}
RISC-V extension modules may be included by an implementor interested
in optimizing a design for one or more purposes.
Available extension modules include M (integer math), A (atomic),
F (32--bit floating point), D (64--bit floating point),
Q (128--bit floating point), C (compressed size instructions) and others.
The extension name {\em G} is used to represent the combined set of IMAFD
extensions as is expected to be a common combination.