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MC6809-MC6809E 8-Bit Microprocessor Programming Manual [M6809PM/AD]
© Motorola Inc., 1981

APPENDIX E - ASCII CHARACTER SET

E.1 INTRODUCTION

This appendix contains the standard 112 character ASCII character set (7-bit code).

E.2 CHARACTER REPRESENTATION AND CODE IDENTIFICATION

The ASCII character set is given in Figure E-1.

Figure E-1. ASCII Character Set
b7 0 0 0 0 0 1 0 1 0 0 1 1 1 0 0 1 0 1 1 1 0 1 1 1
  b6
  b5
b4
b3
b2
b1
Column 0 1 2 3 4 5 6 7
Row Hex 0 1 2 3 4 5 6 7
0 0 0 0 0 0 NUL DLE SP 0 @ P ` p
0 0 0 1 1 1 SOH DC1 ! 1 A Q a q
0 0 1 0 2 2 STX DC2 " 2 B R b r
0 0 1 1 3 3 ETX DC3 # 3 C S c s
0 1 0 0 4 4 EOT DC4 $ 4 D T d t
0 1 0 1 5 5 ENQ NAK % 5 E U e u
0 1 1 0 6 6 ACK SYN & 6 F V f v
0 1 1 1 7 7 BEL ETB ' 7 G W g w
1 0 0 0 8 8 BS CAN ( 8 H X h x
1 0 0 1 9 9 HT EM ) 9 I Y i y
1 0 1 0 10 A LF SUB * : J Z j z
1 0 1 1 11 B VT ESC + ; K [ k {
1 1 0 0 12 C FF FS , < L \ l |
1 1 0 1 13 D CR GS - = M ] m }
1 1 1 0 14 E SO RS . > N ^ n ~
1 1 1 1 15 F SI US / ? O _ o DEL

Each 7-bit character is represented with bit seven as the high-order bit and bit one as the low-order bit as shown in the following example:

b7b6b5b4 b3b2b1b0
1 0 0 0 0 0 0 1

The bit representation for the character "A" is developed from the bit pattern for bits seven through five found above the column designated 4 and the bit pattern for bits four through one found to the left of the row designated 1.

A hexadecimal notation is commonly used to indicate the code for each character. This is easily developed by assuming a logic zero in the non-existant bit eight position for the column numbers and using the hexadecimal number for the row numbers.

E.3 CONTROL CHARACTERS

The characters located in columns zero and one of Figure E-1 are considered control characters. By definition, these are characters whose occurrance in a particular context initiates, modifies, or stops an action that affects the recording, processing, transmission, or interpretation of data. Table E-1 provides the meanings of the control characters.

Table E-1. Control Characters
MnemonicMeaning
NULNull
SOHStart of Heading
STXStart of Text
ETXEnd of Text
EOTEnd of Transmission
ENQEnquiry
ACKAcknowledge
BELBell
BSBackspace
HTHorizontal Tabulation
LFLine Feed
VTVertical Tabulation
FFForm Feed
CRCarriage Return
SOShift Out
SIShift In
DLEData Link Escape
DC1Device Control 1
DC2Device Control 2
DC3Device Control 3
DC4Device Control 4
NAKNegative Acknowledge
SYNSynchronous Idle
ETBEnd of Transmission Block
CANCancel
EMEnd of Medium
SUBSubstitute
ESCEscape
FSFile Separator
GSGroup Separator
RSRecord Separator
USUnit Separator
DELDelete

E.4 GRAPHIC CHARACTERS

The characters in columns two through seven are considered graphic characters. These characters have a visual representation which is normally displayed or printed. These characters and their names are given in Table E-2.

Table E-2. Graphic Characters
SymbolName
SPSpace (Normally Nonprinting)
!Exclamation Point
"Quotation Marks (Diaeresis)
#Number Sign
$Dollar Sign
%Percent Sign
&Ampersand
'Apostrophe (Closing Single Quotation Mark; Acute Accent)
(Opening Parenthesis
)Closing Parenthesis
*Asterisk
+Plus
,Comma (Cedilla)
-Hyphen (Minus)
.Period (Decimal Point)
/Slant
0...9Digits 0 Through 9
:Colon
;Semicolon
<Less Than
=Equals
>Greater Than
?Question Mark
@Commercial At
A...ZUppercase Latin Letters A Through Z
[Opening Bracket
\Reverse Slant
]Closing Bracket
^Circumflex
_Underline
`Opening Single Quotation Mark (Grave Accent)
a...zLowercase Latin Letters a Through z
{Opening Brace
|Vertical Line
}Closing Brace
~Tilde

© Motorola Inc., 1981 (now Freescale as of 2006)
Transferred into HTML by Matthias "Maddes" Bücher in 2006, 2007.
Use all information at your own risk.

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