\documentstyle[art11,fullpage]{article}
\title{X}
\author{}
\date{\today}
%\input{abbrev.tex}
\input{comm}

\begin{document}

{\Huge

\fbox{Representing Characters}
\bi
\item[]
\item {\bf ASCII:} American Standard Code for Information Interchange
\item EBCDIC: Extended Binary Coded Decimal Interchange Code (IBM)
\item ASCII: Fits in one byte but is a 7-bit code
\item $2^7 = 128_{10}$ characters
\item 95 printable characters
\item 33 control characters for communications and peripheral interface
controls 
\item A = $41_h$ ; Z = $5A_h$ ; a = $61_h$; z = $7A_h$
\item Adding $32_{10} = 20_h$  converts from Upper case to Lower case for the
letters of the alphabet
\ei

\newpage

\bi
\item[]
\item[]
\item[] B = $42_h = 0100\; 0010$
\item[] b = $62_h = 0110\; 0010$
\item Lower-order 4 bits are the same
\item[]
\item[] ASCII DIGIT $8_{10} = 38_h = 0011 \; 1000$
\item Lower-order 4bits (nibble) $1000_2 = 8_{10}$
\item []
\item Control Characters
	\be
	\item BEL = $07_h$  (Ring bell)
	\item BS  = $08_h$  (Backspace)
	\item HT  = $09_h$  (Horizontal tab)
	\item LF  = $0A_h$  (Line Feed)
	\item FF  = $0C_h$  (Form Feed)
	\item CR  = $0D_h$  (Carriage Return)
	\ee
\ei

\newpage

\fbox{Bit Manipulation}
\bi
\item[]
\item[] Upper to Lower case: Change bit 5 from 0 to 1
\item[] Test if even or odd integer
\item YOU must learn how to do BIT OPERATIONS
\item[]
\item {\bf Masks:} A sequence of bits designed to target a set of bits in
another number 
\item You already know the truth tables for {\bf NOT, OR, AND, EOR}
\item Bit value 1 == TRUE
\item Bit value 0 == False
\item[]
\ei

\newpage

\be
\item The AND operation sets the bits of X to 0 for 0 in the mask. For bits 1
in the mask, the bits of X are unchanged. X = AC26, MASK (M) = FF00
\item[]	X AND M = AC00
\item[]
\item The OR operation sets the bits of X to 1 for 1 in the MASK. For bits 0
in the mask, the bits of X are unchanged
\item[] X OR M = FF26
\item[]
\item The EOR operation reverses the bits of X for 1 in the mask. For bits  0
in the mask, the bits of X are unchanged
\item[] X EOR M = 5326
\item[]
\item Store value 5 in bits 3 to 5 of an 8-bit register R without affecting the
rest of the bits in R
\ee


}  % end HUGE
\end{document}
