From e2e78a88fd1ffc65b44cd39fd860ac1dfe6ad9cb Mon Sep 17 00:00:00 2001
From: Garritt McCune <glmccune@gmail.com>
Date: Mon, 19 Aug 2024 19:21:49 -0500
Subject: [PATCH] Started the section on the supported interrupts just to get a
 few thoughts down.

---
 chapter 2.tex | 18 ++++++++++--------
 chapter 3.tex | 10 ++++++++++
 document.tex  |  1 +
 3 files changed, 21 insertions(+), 8 deletions(-)
 create mode 100644 chapter 3.tex

diff --git a/chapter 2.tex b/chapter 2.tex
index 496e891..00636ee 100644
--- a/chapter 2.tex	
+++ b/chapter 2.tex	
@@ -28,14 +28,14 @@ Instructions are variable width with their total length being determined by the
 	\begin{tikzpicture}
 		%Opcode Byte
 		\draw (\minX, 0) -- (\lnWidth, 0) node[midway, below=1em] {Opcode};
-		\draw (\minX, \minY) -- (\minX, \maxY) node[above] {7};
-		\draw (\lnWidth, \minY) -- (\lnWidth, \maxY) node[above] {0};
+		\draw (\minX, \minY) node[below] {7} -- (\minX, \maxY);
+		\draw (\lnWidth, \minY) -- (\lnWidth, \maxY) node[above] {7};
 		%Mode setting byte
-		\draw (\lnWidth, 0) -- (\lnWidth * 2, 0) node[midway, below=1em] (ModeByteLabel) {Mode};
-		\draw node[below of=ModeByteLabel] {(if required)};
-		\draw (\lnWidth, \minY) node[below] {7} -- (\lnWidth, \maxY);
+		\draw (\lnWidth, 0) -- (\lnWidth * 2, 0) node[midway, above=1em] (ModeSettingByteLabel) {Mode};
+		\draw node[above of=ModeSettingByteLabel] {(if required)};		
+		\draw (\lnWidth, \minY) node[below] {0} -- (\lnWidth, \maxY);
 		\draw (\lnWidth * 2, \minY) node[below] {0} -- (\lnWidth * 2, \maxY);
-		\draw (\lnWidth + \lnWidth / 2, \minY) -- (\lnWidth + \lnWidth / 2, \maxY) node[above] {4 3};
+		\draw (\lnWidth + \lnWidth / 2, \minY) node[below] (ModeByteMiddleLabel) {4 3} -- (\lnWidth + \lnWidth / 2, \maxY);
 		%Operand One
 		\draw (\lnWidth * 2, 0) -- (\lnWidth * 3, 0) node[midway, below=1em] (OperOneLabel) {Operand One};
 		\draw (\lnWidth * 2, \minY) -- (\lnWidth * 2, \maxY) node[above] {31/15/7};
@@ -125,5 +125,7 @@ The /r represents a byte that specifies a register. /iX is for the immediate dat
 \OpcodeTable{01}{cli}{None}{None}{Clears the interrupt flag preventing the processor from receiving interrupts.}
 \subsection{ENI}
 \OpcodeTable{01}{eni}{None}{None}{Sets the interrupt flag allowing the processor to receive interrupts.}
-\subsection{INT}
-\OpcodeTable{01 /i8}{int /i8}{Immediate}{None}{Triggers software interrupt number \textit{Operand 1}.}
\ No newline at end of file
+\subsection{INT}\label{int}
+\OpcodeTable{01 /i8}{int /i8}{Immediate}{None}{Triggers software interrupt number \textit{Operand 1}.}
+\subsection{LIVT}\label{livt}
+\OpcodeTable{00 /mod /i32}{livt /i32}{Immediate}{None}{Installs the Interrupt Vector Table located at memory address \textit{Operand 1}.}
\ No newline at end of file
diff --git a/chapter 3.tex b/chapter 3.tex
new file mode 100644
index 0000000..7cf9684
--- /dev/null
+++ b/chapter 3.tex	
@@ -0,0 +1,10 @@
+\chapter{Interrupts}
+Interrupts are signals sent to the processor via the I/O pin, software interrupt (via the \ref{int} instruction) or by the processor detecting a fault (divide by zero for instance). When an interrupt occurs the processor will index the Interrupt Vector Table whose location is provided by the livt \ref{livt} instruction.
+
+\paragraph{Unknown Opcode} Interrupt 0. Pushes status flags and clears interrupts.
+
+\paragraph{Divide by Zero} Interrupt 1. Pushes status flags and clears interrupts.
+
+\paragraph{INT 2-31} Reserved for future use.
+
+\paragraph{INT 32-255} Open to be used by software services.
\ No newline at end of file
diff --git a/document.tex b/document.tex
index f4dd25c..f8b8baa 100644
--- a/document.tex
+++ b/document.tex
@@ -17,5 +17,6 @@
 	\tableofcontents
 	\include{chapter 1}
 	\include{chapter 2}
+	\include{chapter 3}
 	
 \end{document}
\ No newline at end of file